title: UICollectionView doesn't contain UICollectionViewCell in IB
body: <p>I'm trying to add a UICollectionView to a .nib file in IB. I've worked through a few tutorials and had no problems.</p>
  
  <p>In my existing app, when I drag a collection view into a view in IB and then expand the object, the CollectionView Flow Layout is there , but there is no collection view cell. I also cannot drag and drop a cell into the collection view. Also the collection view is displayed differently, showing an image of a grid of cells instead of the normal white box.</p>
  
  <p>I've tried creating a new view controller with nib, and have the same results when adding a collectionView.</p>
  
  <p>This app WAS targeting iOS 4.2, but I've changed the deployment target to iOS 6.</p>
  
  <p>In any newly created projects I don't get this behavior.</p>