title: hist and axvline do not follow color cycle / matplotlib style
body: <p>I'm trying to plot a distribution and it's mean:</p>
  
  <pre><code>import matplotlib.pyplot as plt
  import numpy as np
  plt.style.use('ggplot')
  
  numbers = np.random.rand(100)
  fig, ax = plt.subplots()
  ax.hist(numbers)
  ax.axvline(numbers.mean())
  </code></pre>
  
  <p>which will plot a red line on top of a red distribution. Importantly, I want to use the colors from my color scheme (<code>gglot</code>), and hence I do not want to manually select colors, or even a color cycle. </p>
  
  <p><a href="https://stackoverflow.com/a/50701379/1082349">Recently</a>, I learned that if I want to "force" the color cycler to use the next color, I can do </p>
  
  <pre><code>next(ax._get_lines.prop_cycler)
  </code></pre>
  
  <p>However, adding that line in between the hist and axvline does not help here. How could I "force" <code>hist</code> and <code>axvline</code> to follow the colors from my style?</p>