UICollectionViewLayout自定义布局收集整理：
- CircleLayout: https://developer.apple.com/library/content/samplecode/CircleLayout/Introduction/Intro.html#//apple_ref/doc/uid/DTS40012315-Intro-DontLinkElementID_2
- EBCardCollectionViewLayout: https://github.com/betzerra/EBCardCollectionViewLayout
- HJCarouselDemo: https://github.com/panghaijiao/HJCarouselDemo
- INSElectronicProgramGuideLayout: https://github.com/inspace-io/INSElectronicProgramGuideLayout
- ShowQuotations: https://github.com/KaiZhang890/ShowQuotations
- KTCenterFlowLayout: https://github.com/keighl/KTCenterFlowLayout
- SBCollectionViewFlowLayout: https://github.com/c0ming/SBCollectionViewFlowLayout
- YRCoverFlowLayout: https://github.com/solomidSF/YRCoverFlowLayout
- ZLBalancedFlowLayout: https://github.com/zhxnlai/ZLBalancedFlowLayout
- NHBalancedFlowLayout: https://github.com/njdehoog/NHBalancedFlowLayout
- RACollectionViewReorderableTripletLayout: https://github.com/ra1028/RACollectionViewReorderableTripletLayout
- RGCardViewLayout: https://github.com/terminatorover/RGCardViewLayout
- StickyCollectionView: https://github.com/matbeich/StickyCollectionView
- UICollectionViewLeftAlignedLayout: https://github.com/mokagio/UICollectionViewLeftAlignedLayout
- FMMosaicLayout: https://github.com/fmitech/FMMosaicLayout