title: R reshape wide, change timevar order
body: <p>I am using the reshape function on a date field and wonder if there is a way to change the order that fields are listed in the reshaped table.
  I tried sorting the original table before the reshape but it didn't work.</p>
  
  <pre><code>DQ_Summary= data.frame(RuleID=c(1,2,1,2),
                        ProcessorTimeStamp=as.Date(c('2016-08-04','2016-08-04','2016-08-08','2016-08-08')),
                        ErrorCount=c(6,8,3,4))
  
  #   RuleID ProcessorTimeStamp ErrorCount
  # 1      1         2016-08-04          6
  # 2      2         2016-08-04          8
  # 3      1         2016-08-08          3
  # 4      2         2016-08-08          4
  
  Final_Summary = reshape(DQ_Summary,
                          timevar = "ProcessorTimeStamp",
                          idvar = c("RuleID"),
                          direction = "wide")
  </code></pre>
  
  <p>The above code returns a table that is formatted like:</p>
  
  <pre><code>#   RuleID ErrorCount.2016-08-04 ErrorCount.2016-08-08
  # 1      1                     6                     3
  # 2      2                     8                     4
  </code></pre>
  
  <p>I would like to see the order of the fields reshaped fields reversed:</p>
  
  <pre><code>#   RuleID ErrorCount.2016-08-08 ErrorCount.2016-08-04
  # 1      1                     3                     6
  # 2      2                     4                     8
  </code></pre>
  
  <p>It may seem trivial but it is something I need to have.</p>