title: Adding units to heatmap annotation in Seaborn
body: <p>I am trying to show a table of percentages as a heatmap in Seaborn:</p>
  
  <pre><code>sns.heatmap(S, annot=True, fmt=".1f", linewidths=1.0, square=1)
  </code></pre>
  
  <p>However, I'd like the percent sign to appear after each number in the heatmap annotations. The <code>fmt</code> flag only seems to accept number format specifiers. Is there a way to do this either within Seaborn or with some matplotlib tweaking?</p>