title: TortoiseHg not deleting files on update + clean
body: <p>I performed these steps:</p>
  
  <ol>
  <li>Commited my project</li>
  <li>Added a couple class files to my project</li>
  <li>Decided I wanted to completely abandon what I had just done</li>
  <li>Used TortoiseHg Repository Explorer to Update to last changeset with "Discard local changes, no backup (-C/--clean)" checked/turned on</li>
  </ol>
  
  <p>The two class files I added did not get deleted as I would have expected. They appear in the folder without shell icons.</p>
  
  <p><strong>Questions</strong></p>
  
  <ol>
  <li>Is this correct behavior or a bug?</li>
  <li>If this is correct, is there a feature that will allow me to go back to a previous changeset without ending up with a bunch of junk files in my working copy?</li>
  </ol>