Improved implementation of indexPathsForVisibleItems
Improved implementation of indexPathsForVisibleItems

Kevin775263419/PSTCollectionView,zace-yuan/PSTCollectionView,thevuuranusls/PSTCollectionView,Anish-kumar-dev/PSTCollectionView,godLoveLucifer/PSTCollectionView,niuxinghua/PSTCollectionView,ba01ei/PSTImprovedCollectionView,StephaneDelcroix/PSTCollectionView,jianwoo/PSTCollectionView,Amnysia/PSTCollectionView,zjh171/PSTCollectionView,StephaneDelcroix/PSTCollectionView,steipete/PSTCollectionView,CorzFree/PSTCollectionView