Merge branch 'hotfix/fix_array_init' into develop
[Fix] shouldInvalidateLayoutForBoundsChange
Call [self commonInit] also in initWithCoder:

When using Nibs / storyboards for initializing the layout, initWithCoder
is the designated initializer.
Section header and/or footer should work properly
Call [super initWithCoder] instead of init
Merge branch 'develop' of https://github.com/amaechler/CHTCollectionViewWaterfallLayout into amaechler-develop
Change some properties and methods to imitate UICollectionViewFlowLayout's usage as much as possible
- Don't need to calculate item size by yourself.
- Also fix some issues with frame calculation.
Update podspec and README
Merge branch 'release/0.6'