shuffle.py v1.3

Full Changelog:

* Directory based auto playlist building (--auto-dir-playlists) (#13)
* ID3 tags based auto playlist building (--auto-id3-playlists)
* Added short program description
* Fix hyphen in filename #4
* Fixed mutagen bug #5
* Voiceover disabled by default #26 (Playlist voiceover enabled with auto playlist generation)
* Differentiate track and playlist voiceover #26