title: Xcode7.3 swift project lost syntax coloring
body: <p>My swift project has good syntax coloring on Xcode7.2, after I updated to Xcode7.3, syntax coloring has gone, except strings, numbers, and comments. And the shortcut keys "command+/" to comment is not working either. So is autocompletion. I created a new swift project, and it has the same problem. But Objective-c projects are working well. </p>
  
  <p>I searched and tried deleting derived data, not working. </p>
  
  <p>Another thing is throught Editor > Syntax Coloring, I cannot find Swift.</p>