jwilling/JNWCollectionView — pull request #94 by allright (2014-01-24 13:29:24+00:00)
Title: debug assert

Please add some debug warnings here, I lost some time trying to enable headers on JNWCollectionViewGridLayout.
The reason was a typo that I used JNWCollectionViewListLayoutHeaderKind instead of JNWCollectionViewGridLayoutHeaderKind.