Design
------

Dub Playlist
------------

Dub considers the filesystem as its database. User specifies one or more
directories as the directories in which dub will scan for all or particular
media types.

The scanning is initiated on demand, so that dub does not perform redundant
disk access which is expensive.

Design Goals
------------

v1.0
----

User interface:

 * settings: select directories that contain media files.

 * list/tree view to browse files: this should scan directories like a file
manager would, consider re-using code from elsewhere

 * add file: symlink to a directory as Njaard suggests

v2.0
----

implement filters: directory-wise filtering of media types.

implement database: for storing properties of media files, such as tags in
mp3s so that alternative queries can be made.

user interface: improved tree view that accesses the db to fetch info
about files

v3.0
----

music playing: implement an automated dj process.
