title: SectionIndexTitles for a UICollectionView
body: <p>So I implemented a proper <code>TableView</code> with a search functionality and <code>sectionIndexTitles</code>. Now, I am trying to implement a <code>UICollectionView</code> and it is working so far, except that I can't easily have <code>sectionIndexTitles</code> (the right scroll bar).</p>
  
  <p>If I look at the Facebook Application, it looks like a <code>UICollectionView</code>, but with indeed <code>sectionIndexTitles</code> and a searchbar. I can't seem to find such functions for the <code>UICollectionView</code> model.</p>
  
  <p>Any ideas?!</p>
  
  <p>Thanks!</p>
  
  <p><img src="https://i.stack.imgur.com/ekafI.jpg" alt="enter image description here"></p>