title: Git Cherry Pick dirty index
body: <p>I have two branches master and exp</p>
  
  <p>i tried to cherry pick some of the commit in the exp to master.I am getting
  the following error.</p>
  
  <pre><code>git cherry-pick 209c4b154d3c15fa8086d4cc15fa34e53b8a65a3
  fatal: Dirty index: cannot cherry pick
  </code></pre>
  
  <p>Can anyone explain this error.</p>