* Allow UICollectionViewLayout to give us a layout inspector, always call the didChangeDelegate/didChangeDataSource on binding
* Make an assertion
* Update the tests
* Tests use actual layout inspector
* Be more consistent
* Reimplement IGListKit support in a cleaner way
* Rename and fix some stuff
* Fix supplementaries more
* Update docs
* Update test
* Cleanup minor things
* Tweak it
* Indentation
* Remove irrelevant changes
* Break out cell into its own file
* Fix indentation
* Address feedback