title: Plot dotted line in seaborn factorplot
body: <pre><code>import seaborn as sns
  sns.set(style="ticks")
  exercise = sns.load_dataset("exercise")
  g = sns.factorplot(x="time", y="pulse", hue="kind", data=exercise)
  </code></pre>
  
  <p>In the plot above, is there a way to plot one of the line types as a dotted line, e.g. plot the 'rest' line as dotted.</p>