title: GIT submodules in android project causes "Unable to ignore resources" error
body: <p>I am using eclipse with ADT. Also I have android project with GIT submodules. Until I updated ADT this works very well. I don't clearly remember last ADT version, but it is about 18. Since I updated ADT I get this errors:</p>
  
  <pre><code>java.lang.IllegalArgumentException: Attempted to beginRule: F/Project/ActionBarSherlock/actionbarsherlock/gen, does not match outer scope rule: MultiRule[F/actionbarsherlock/gen]
  </code></pre>
  
  <p>with message:</p>
  
  <pre><code>Unable to ignore resources
  </code></pre>
  
  <p>Sometimes I can't export signet package, but this is totally random case, because after a fail I restart Eclipse and try again and in 3-5 attempts it works. But this procedure very annoying me.</p>
  
  <p>How I can deal with it?</p>