Add deselect selector to proxy

Summary:
Issue fixed: #1105

- [x] All tests pass. Demo project builds and runs.
- [ ] ~~I added tests, an experiment, or detailed why my change isn't tested.~~
- [x] I added an entry to the `CHANGELOG.md` for any breaking changes, enhancements, or bug fixes.

Unable to add tests w/out hacking `UITouch` events on a collection view. Open to suggestions.
Closes #1108

Differential Revision: D7362200

Pulled By: rnystrom

fbshipit-source-id: fed640c2c017f0ade0cefff0b0d2118564dda3b0

CHANGELOG.md

@@ -16,6 +16,8 @@ The changelog for `IGListKit`. Also see the [releases](https://github.com/instag
 
 - Fixed footer is sticky when `stickyHeader` is `true` [aelam](https://github.com/aelam) [(#1094)](https://github.com/Instagram/IGListKit/pull/1094)
 
+- `-[IGListSectionController didSelectItemAtIndex:]` is now called when a `scrollViewDelegate` or `collectionViewDelegate` is set. [Ryan Nystrom](https://github.com/rnystrom) [(#1108)](https://github.com/Instagram/IGListKit/pull/1108)
+
 3.2.0
 -----
 

Source/Internal/IGListAdapterProxy.m

@@ -27,6 +27,7 @@ static BOOL isInterceptedSelector(SEL sel) {
             sel == @selector(collectionView:willDisplayCell:forItemAtIndexPath:) ||
             sel == @selector(collectionView:didEndDisplayingCell:forItemAtIndexPath:) ||
             sel == @selector(collectionView:didSelectItemAtIndexPath:) ||
+            sel == @selector(collectionView:didDeselectItemAtIndexPath:) ||
             sel == @selector(collectionView:didHighlightItemAtIndexPath:) ||
             sel == @selector(collectionView:didUnhighlightItemAtIndexPath:) ||
             // UICollectionViewDelegateFlowLayout