Fixing logic about UIImageView's completion handler
Fixing logic about UIImageView's completion handler

Reference:
https://github.com/hirohisa/ImageLoader

hirohisa/ImageLoaderSwift,oenius/ImageLoaderSwift,iAladdin/ImageLoaderSwift,ton-katsu/ImageLoaderSwift,glustful/ImageLoaderSwift,hirohisa/ImageLoaderSwift,ton-katsu/ImageLoaderSwift,etataurov/ImageLoaderSwift,glustful/ImageLoaderSwift,iAladdin/ImageLoaderSwift,etataurov/ImageLoaderSwift,oenius/ImageLoaderSwift,valentinmaxime/ImageLoaderSwift,valentinmaxime/ImageLoaderSwift