title: Mercurial ignore part of a directory
body: <p>Been fighting with Mercurial's .hgignore for a while under Windows.</p>
  
  <p>I have a folder named Upload which is currently empty.  I do want it tracked so I added a .empty file in it which work fine.  I want this so that new developers doing an hg clone get the Upload document required for the application.</p>
  
  <p>Thing is I never want the folder to be populated with anything on the source control itself (test uploads from a development machine).</p>
  
  <p>Example:
  If I add Public/image.jpg it wouldn't be tracked.</p>
  
  <p>Additionally I would like it for sub directory to be tracked.  So if  developer adds</p>
  
  <p>Upload/users/.empty I would like this to be tracked.</p>
  
  <p>Is this possible with regex voodoo?</p>