[feature/nestedset-album] Use nestedset in album_base
[feature/nestedset-album] Adjust unit tests and use scope prototype for albums
[feature/nestedset-album] Use new nestedset tree class from the core
[feature/nestedset-album] Add nestedset methods to the album base class
[feature/nestedset-album] Fix tests
[feature/nestedset-album] Move test files to new directory
[feature/nestedset-album] Update class_loader to newest behaviour
[feature/nestedset-album] Add unit tests for wrappers around nestedset
[feature/nestedset-album] Change thrown exceptions to default exceptions
[feature/nestedset-album] Add category type to create album test
[feature/nestedset-album] Add delete method to interface and base class
[feature/nestedset-album] Fix thrown exceptions
[feature/nestedset-album] Make type validation public
[feature/nestedset-album] Add tree methods to interface
[feature/nestedset-album] Add methods for containing and uploading images
[feature/nestedset-album] Add tests for can_*_images()
Merge branch 'feature/nestedset-album' into develop