Design overview: PlaylistManager

[Bart Cerneels]

This is an overview of the
PlaylistManager/Meta::Playlist/Synchronization in Amarok as a
preparation for the Amarok DevSprint in Berlin, May 1.

Classes (function):
- Meta::Playlist (abstract base of all playlists)
- PlaylistManager (Facility for managing PlaylistProviders registered
by other parts of the application, plugins or scripts)
- PlaylistProvider (abstract base that gives playlists, description
and friendlyname for once playlist category)

Related classes in browsers/playlistbrowser not covered in this overview
- PodcastCategory/PodcastModel
- PlaylistCategory/UserPlaylistModel
- PlaylistsInGroupsProxy
...

Next mail: functional overview

Bart