Merge dev to master branch

Conflicts:
	ALAssetsLibrary-CustomPhotoAlbum/ALAssetsLibrary+CustomPhotoAlbum.h
	ALAssetsLibrary-CustomPhotoAlbum/ALAssetsLibrary+CustomPhotoAlbum.m
	Demo/ALAssetsLibraryCustomPhotoAlbum_BasicDemo/ALAssetsLibraryCustomPhotoAlbum_BasicDemo/ALAssetsLibraryCustomPhotoAlbum_BasicDemo-Info.plist
	Demo/ALAssetsLibraryCustomPhotoAlbum_BasicDemo/ALAssetsLibraryCustomPhotoAlbum_BasicDemo/Controllers/PhotoViewController.m
	Demo/ALAssetsLibraryCustomPhotoAlbum_BasicDemo/ALAssetsLibraryCustomPhotoAlbum_BasicDemo/Controllers/PhotosTableViewController.m
	README.md