swift Storyboardを使わずにCollectionView UICollectionview with custom cell メモリリーク
http://www.techotopia.com/index.php/A_Swift_iOS_8_Storyboard-based_Collection_View_Tutorial
http://www.tk4memo.info/swift%E3%81%A7collectionview%E3%82%92%E3%81%A8%E3%82%8A%E3%81%82%E3%81%88%E3%81%9A%E8%A1%A8%E7%A4%BA%E3%81%95%E3%81%9B%E3%81%A6%E3%81%BF%E3%82%8B/
メモリリークについても
http://chicketen.blog.jp/archives/15787549.html
http://www.seemuapps.com/tutorial-uicollectionview-with-custom-cell
http://swiftiostutorials.com/tutorial-creating-custom-layouts-uicollectionview/
http://www.ioscreator.com/tutorials/custom-collection-view-cell-tutorial-ios8-swift