implement initial architecture for separating data storage
add memory storage methods for data models, refactor naming.
fix naming problems, fix typos
use DTModelStorage pod. Remove tests for memory storage - they are now located in DTModelStorage repo.
start rewriting tests to support DTModelStorage, remove old stuff.
moved tests to new architecture. Failing for now.
Fix some example issues with new architecture.
fix examples. Add workarounds for header and footer reference size for flow layout
disable all collection view animations temporarily.
fix mapping test
implemented partial fix for UICollectionView performUpdates bug.
fix unit tests with item insertion.
implement moving collection view items. Added section and item animation blocks.
reimplemented moving items, added workarounds for empty sections, existing sections, and removing last item.
implement moving sections.
move item more safely
remove old workarounds, restructure new ones.
fix unit tests iOS 7 issue with supplementary headers
use console specs for test runner
use NSInteger instead of int.