title: "Copy Local" does not copy assemblies to output directory
body: <p>I have an assembly X that is referencing <code>System.Interactive</code> and <code>System.Reactive</code> from a lib folder.
  Then I have assembly Y that is referencing X.</p>
  
  <p>In X for both, <code>System.Interactive</code> and <code>System.Reactive</code>, 'Copy Local' is set to true.
  In Y for X 'Copy Local' is set to true.
  <code>System.Reactive</code> and <code>System.Interactive</code> are not in the GAC.</p>
  
  <p>When I build Y, <code>System.Interactive</code> and <code>System.Reactive</code> are not copied to the output directory. Why?</p>