title: Can't transition title or transition time depending on using transition_states or transition_times in new version of gganimate
body: <p>I have been playing with the new version of gganimate, I tend to use animations a lot in my classes. I am trying to build a graph that shows how Nitrous oxide changes over time in a station in Spain. I want two features in the animations</p>
  
  <ol>
  <li>Stop for a while at each year</li>
  <li>Have the year in the title for each time</li>
  </ol>
  
  <p>I have been able to build this two graphs using the following data</p>
  
  <pre><code>Madrid3 &lt;- structure(list(month = c(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 
                       1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 1, 2, 3, 4, 5, 6, 7, 8, 
                       9, 10, 11, 12, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 1, 2, 3, 
                       4, 5, 6, 7, 8, 9, 10, 11, 12, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 
                       11, 12, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 1, 2, 3, 4, 5,  
                       6, 7, 8, 9, 10, 11, 12), name = c("Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                         "Cuatro Caminos", "Cuatro Caminos"), year = c(2010, 2010, 2010, 
                                                                                                       2010, 2010, 2010, 2010, 2010, 2010, 2010, 2010, 2010, 2011, 2011, 
                                                                                                       2011, 2011, 2011, 2011, 2011, 2011, 2011, 2011, 2011, 2011, 2012, 
                                                                                                       2012, 2012, 2012, 2012, 2012, 2012, 2012, 2012, 2012, 2012, 2012, 
                                                                                                       2013, 2013, 2013, 2013, 2013, 2013, 2013, 2013, 2013, 2013, 2013, 
                                                                                                       2013, 2014, 2014, 2014, 2014, 2014, 2014, 2014, 2014, 2014, 2014, 
                                                                                                       2014, 2014, 2015, 2015, 2015, 2015, 2015, 2015, 2015, 2015, 2015, 
                                                                                                       2015, 2015, 2015, 2016, 2016, 2016, 2016, 2016, 2016, 2016, 2016, 
                                                                                                       2016, 2016, 2016, 2016, 2017, 2017, 2017, 2017, 2017, 2017, 2017, 
                                                                                                       2017, 2017, 2017, 2017, 2017), NO_2 = c(52.7411978235155, 49.9936308697576, 
                                                                                                                                               45.3346567988235, 42.7514465030941, 35.8548923634714, 47.1773919094889, 
                                                                                                                                               53.7143816896664, 41.9823522292158, 63.525647942449, 72.838654011127, 
                                                                                                                                               67.8730001012484, 74.422916644363, 72.6258411843876, 82.929955290611, 
                                                                                                                                               54.8495702005731, 52.7180555555556, 46.2647849462366, 50.0291666666667, 
                                                                                                                                               41.483039348711, 39.4808510638298, 57.9651324965132, 58.7177419354839, 
                                                                                                                                               51.3212795549374, 54.7997311827957, 65.4245283018868, 52.0502873563218, 
                                                                                                                                               46.5370121130552, 28.3212795549374, 35.5846774193548, 28.4361111111111, 
                                                                                                                                               31.822102425876, 26.3978494623656, 39.7367688022284, 57.5685483870968, 
                                                                                                                                               50.7777777777778, 59.7415881561238, 52.8936742934051, 48.1741071428571, 
                                                                                                                                               34.8891891891892, 36.7805555555556, 34.9381720430108, 33.1390820584145, 
                                                                                                                                               38.257065948856, 29.1467025572005, 46.3147632311978, 48.7190860215054, 
                                                                                                                                               48.9763560500695, 66.9152086137281, 45.5302826379542, 40.3288690476191, 
                                                                                                                                               46.7063599458728, 36.5340751043115, 34.25, 34.5805555555556, 
                                                                                                                                               33.1009421265141, 25.4072580645161, 38.3157162726008, 52.9743243243243, 
                                                                                                                                               47.8969359331476, 66.6617250673854, 70.5094594594595, 39.5111773472429, 
                                                                                                                                               47.6205962059621, 30.6193820224719, 32.2088948787062, 35.2154929577465, 
                                                                                                                                               35.3301886792453, 24.688679245283, 37.933147632312, 46.2293080054274, 
                                                                                                                                               65.5738161559889, 73.0350404312669, 44.7102425876011, 39.2126436781609, 
                                                                                                                                               37.7466307277628, 34.9527777777778, 32.7379032258064, 33.7051460361613, 
                                                                                                                                               35.6263440860215, 28.3189771197847, 46.3207810320781, 55.5389784946237, 
                                                                                                                                               54.9066852367688, 66.5080862533693, 59.8812415654521, 46.010447761194, 
                                                                                                                                               43.7183288409704, 34.3513888888889, 33.4, 35.7649513212796, 33.9986486486486, 
                                                                                                                                               26.2876344086022, 43.5251396648045, 59.6370967741936, 73.4442896935933, 
                                                                                                                                               60.0040431266846), n = c(743L, 672L, 744L, 720L, 744L, 720L, 
                                                                                                                                                                        744L, 744L, 720L, 744L, 720L, 744L, 743L, 672L, 720L, 720L, 744L, 
                                                                                                                                                                        720L, 744L, 720L, 720L, 744L, 720L, 744L, 743L, 696L, 744L, 720L, 
                                                                                                                                                                        744L, 720L, 744L, 744L, 720L, 744L, 720L, 744L, 743L, 672L, 744L, 
                                                                                                                                                                        720L, 744L, 720L, 744L, 744L, 720L, 744L, 720L, 744L, 743L, 672L, 
                                                                                                                                                                        744L, 720L, 744L, 720L, 744L, 744L, 720L, 744L, 720L, 744L, 743L, 
                                                                                                                                                                        672L, 744L, 720L, 744L, 720L, 744L, 744L, 720L, 744L, 720L, 744L, 
                                                                                                                                                                        743L, 696L, 744L, 720L, 744L, 720L, 744L, 744L, 720L, 744L, 720L, 
                                                                                                                                                                        744L, 743L, 672L, 744L, 720L, 744L, 720L, 744L, 744L, 720L, 744L, 
                                                                                                                                                                        720L, 744L)), row.names = c(NA, -96L), class = c("grouped_df", 
                                                                                                                                                                                                                         "tbl_df", "tbl", "data.frame"), vars = c("month", "name"), .Names = c("month", 
                                                                                                                                                                                                                                                                                               "name", "year", "NO_2", "n"), indices = list(c(0L, 12L, 24L, 
                                                                                                                                                                                                                                                                                                                                              36L, 48L, 60L, 72L, 84L), c(1L, 13L, 25L, 37L, 49L, 61L, 73L, 
                                                                                                                                                                                                                                                                                                                                                                          85L), c(2L, 14L, 26L, 38L, 50L, 62L, 74L, 86L), c(3L, 15L, 27L, 
                                                                                                                                                                                                                                                                                                                                                                                                                            39L, 51L, 63L, 75L, 87L), c(4L, 16L, 28L, 40L, 52L, 64L, 76L, 
                                                                                                                                                                                                                                                                                                                                                                                                                                                        88L), c(5L, 17L, 29L, 41L, 53L, 65L, 77L, 89L), c(6L, 18L, 30L, 
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          42L, 54L, 66L, 78L, 90L), c(7L, 19L, 31L, 43L, 55L, 67L, 79L, 
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      91L), c(8L, 20L, 32L, 44L, 56L, 68L, 80L, 92L), c(9L, 21L, 33L, 
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        45L, 57L, 69L, 81L, 93L), c(10L, 22L, 34L, 46L, 58L, 70L, 82L, 
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    94L), c(11L, 23L, 35L, 47L, 59L, 71L, 83L, 95L)), group_sizes = c(8L, 
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L), biggest_group_size = 8L, labels = structure(list(
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        month = c(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12), name = c("Cuatro Caminos", 
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos", 
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   "Cuatro Caminos", "Cuatro Caminos", "Cuatro Caminos")), row.names = c(NA, 
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         -12L), class = "data.frame", vars = c("month", "name"), .Names = c("month", 
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            "name")))
  </code></pre>
  
  <h3>Using transition_time</h3>
  
  <p>When I use transition time, using the following code:</p>
  
  <pre><code>ggplot(Madrid2,aes(x = month, y = NO_2)) + stat_smooth(method = "lm", formula = y ~ x + I(x^2), alpha = 0.5,aes(fill = name)) + geom_point() + 
     # Here comes the gganimate code
    transition_time(year) +
    enter_fade() + 
    exit_shrink() +
    ease_aes('linear') + labs(title = 'Year: {round(frame_time,0)}', x = 'Month', y = 'NO_2')
  </code></pre>
  
  <p>I get this image, which is good because I get the years as a title, but I would like the gif to stop for a while on each year. It follows condition 2 but not 1 of my list</p>
  
  <p><a href="https://i.stack.imgur.com/NNhyv.gif" rel="noreferrer"><img src="https://i.stack.imgur.com/NNhyv.gif" alt="enter image description here"></a></p>
  
  <p>So I try the following code:</p>
  
  <pre><code>ggplot(Madrid3,aes(x = month, y = NO_2)) + stat_smooth(method = "lm", formula = y ~ x + I(x^2), alpha = 0.5,aes(fill = name)) + geom_point() + 
    # Here comes the gganimate code
    transition_time(year, state_length = 2, transition_length = 1) +
    enter_fade() + 
    exit_shrink() +
    ease_aes('linear') + labs(title = 'Year: {round(frame_time,0)}', x = 'Month', y = 'NO_2')
  </code></pre>
  
  <p>but I get the following error:</p>
  
  <pre><code> Error in transition_time(year, state_length = 2, transition_length = 1) : 
    unused arguments (state_length = 2, transition_length = 1)
  </code></pre>
  
  <p>So I tried with <code>transition_states</code> instead of <code>transition_times</code></p>
  
  <h2>using transition states</h2>
  
  <p>With transtition_states I have a different problem, it works fine if I do this:</p>
  
  <pre><code>ggplot(Madrid3,aes(x = month, y = NO_2)) + stat_smooth(method = "lm", formula = y ~ x + I(x^2), alpha = 0.5,aes(fill = name)) + geom_point() + 
     # Here comes the gganimate code
     transition_states(year, state_length = 2, transition_length = 1) +
     enter_fade() + 
     exit_shrink() +
     ease_aes('linear') 
  </code></pre>
  
  <p>Which gives me the following graph:</p>
  
  <p><a href="https://i.stack.imgur.com/VaGI2.gif" rel="noreferrer"><img src="https://i.stack.imgur.com/VaGI2.gif" alt="enter image description here"></a></p>
  
  <p>In this case I have the transtition pauses I wanted (condition 1), but I can't get the titles to work (condition 2), I have tried:</p>
  
  <pre><code>ggplot(Madrid3,aes(x = month, y = NO_2)) + stat_smooth(method = "lm", formula = y ~ x + I(x^2), alpha = 0.5,aes(fill = name)) + geom_point() + 
    # Here comes the gganimate code
    transition_states(year, state_length = 2, transition_length = 1) +
    enter_fade() + 
    exit_shrink() +
    ease_aes('linear') + labs(title = 'Year: {round(frame_time,0)}', x = 'Month', y = 'NO_2')
  </code></pre>
  
  <p>Which gives me the following error:</p>
  
  <pre><code>Error in eval(parse(text = text, keep.source = FALSE), envir) : 
     object 'frame_time' not found
  </code></pre>
  
  <p>So then I though, maybe change frame_time to frame_states</p>
  
  <pre><code> ggplot(Madrid3,aes(x = month, y = NO_2)) + stat_smooth(method = "lm", formula = y ~ x + I(x^2), alpha = 0.5,aes(fill = name)) + geom_point() + 
    # Here comes the gganimate code
    transition_states(year, state_length = 2, transition_length = 1) +
    enter_fade() + 
    exit_shrink() +
    ease_aes('linear') + labs(title = 'Year: {round(frame_states,0)}', x = 'Month', y = 'NO_2')
  </code></pre>
  
  <p>But it gives me the following error:</p>
  
  <pre><code>Error in eval(parse(text = text, keep.source = FALSE), envir) : 
    object 'frame_states' not found
  </code></pre>
  
  <p>I am not sure what else to try</p>