Storage Access Framework
https://developer.android.com/guide/topics/providers/document-provider.html
MediaStore
https://developer.android.com/reference/android/provider/MediaStore.html#
ContentResolver
https://developer.android.com/reference/android/content/ContentResolver.html
CursorJoinerを使ってMediaStore.Images.Thumbnailsに回転情報を追加する
http://qiita.com/tomoima525/items/762a55a86b3decf05d55
AndroidImageGallerySample
https://github.com/kaelaela/AndroidImageGallerySample