title: UICollectionView with custom header
body: <p>I'm trying to develop a <em>UICollectionView</em> which supports a custom header containing a UIScrollview. The problem is that (according what I have found so far in the documentation) UICollection view doesn't support static headers view like UITableview (where I could just drop a view inside using storyboard). The header is a <em>UICollectionResusableView</em> instance which gets re-generated every time the Collection View is scrolled up and down. Clearly this kind of view cannot be connected to outlet because is a dynamic prototype like UITableViewCell.
  How I add a custom view (and <strong>relative view controller</strong> which I can wire up) as header of my collection view?</p>
  
  <p>PS. I'm developing on iOS8</p>