Start of rewriting grid view layout code to support additional things
Minor changes
Reenable cell reuse, handle insertions and removals
Don't crash when resetting the view
Properly allow disabling of animations, and changing margins requires a layout invalidation
Resolve some issues with view selection on rotation and other rotation animation issues
The height of each cell needs to be recalculated when the entire layout is invalidated
Properly handle reloadData
Fully support reuse identifiers
Code to support sections
Gives footer hint to available space below content

Only if content is less than total height of scrollview's frame
Fix layout issue on controllers that aren't full width
Merge branch 'feature/incremental-insertion-deletion' of github.com:carsonb/PSCollectionView into feature/sections
Try to position footer properly
Fix for yOffset calculation of sections
Section and section header support
Merge branch 'master' of github.com:carsonb/PSCollectionView into feature/incremental-insertion-deletion

Conflicts:
	PSCollectionView.m
Merge branch 'feature/incremental-insertion-deletion' of github.com:carsonb/PSCollectionView into feature/sections
Properly animation section header frame changes

@carsonb this should fix the animation issue you were seeing
Merge pull request #13 from carsonb/feature/sections

Feature/sections