Achieve UICollectionView's behaviour of allowsMultipleSelection = false

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I am using EmbeddedSection Controller for showing horizontal scrolling list.
I want to have just one selected cell in the horizontal list. (and deselect others when one is selected)
I can see there are two approaches:
1. Iterate over SCs and see which are selected
2. Create delegate that forwards selections/deselections.

However, in a discussion of #184, @rnystrom has mentioned that they are trying to bake support into IGListKit.
What is the best way to do it now? Is there an example?