title: @2x images do not display in XCode4 interface builder designer
body: <p>I'm trying to design a xib using XCode4, but when I put down an image view that displays an @2x image xcode doesn't preview it correctly (it displays a missing image icon).
  It works correctly when the app is run though.</p>
  
  <p>As an example: I add a UIImageView to my view and set the image property to test.png.
  In my project I add a file named test@2x.png.</p>
  
  <p>In XCode 3.2 this image would have correctly displayed in IB, and the @2x version would have automatically half-sized on non-retina devices. </p>
  
  <p>However in IB in XCode4 the image does not display.</p>
  
  <p>Is anyone else experiencing this? If they are, it's a pretty massive issue.</p>