title: Adding a reference to a project not working
body: <p><a href="http://prntscr.com/65pjv1" rel="nofollow">http://prntscr.com/65pjv1</a> - VStudio. In the right you can see the Annotations reference added, down you can see that it has succeeded the built. Also you can see that UsedImplicitly(comming from JetBrains.Annotations) is found.</p>
  
  <p>But unity doesn't think so: <a href="http://prntscr.com/65pjy9" rel="nofollow">http://prntscr.com/65pjy9</a> - error. </p>
  
  <p>This is something very simple, but obviously I am doing smth wrong. What should I change? </p>