Split out framework and demo code into targets
Extra recommended gitignore
Newlines at end of files
Use of "strong" for string properties in demo
Mitigate "implicit capture of self" w/ properties
Variable shadowing warnings
"Floating-point precision" warnings
Misc warnings
Implicit conversion warnings
Math functions to mitigate unsafe float warnings
Fix dastardly empty layout issue
Fix issue with deleting sections in composed data sources
Fix automatic height calculation
Move invalidation context to layout attr. file like UIKit
Leading/trailing layout order support
Useful little inset doodad
Fix layout trace log warning
Preliminary support for generic supplementary views
Minor perf. improvement in layout/kind tuple

Conflicts:
	AdvancedCollectionView/Framework/Layouts/AAPLCollectionViewGridLayout_Internal.m
Don't require sorted arrays of layout attributes