- including mediafile and enumeration modules from the "beets" package. Mediafile
  provides an abstraction layer/wrapper around the mutagen library, which greatly
  simplifies metadata writing capabilities between multiple formats.
- clean up of the Album and Tagger classes. These have been renamed DiscogsAlbum
  and TaggerUtils
- clean up discogs_tagger.py. stripped to the bare minimum.
more rework for version 1.0

- updated setup.py script
- integration with mediafile.py
- tagging is now functional. limited testing..
- embedding of album art.
Should be safe enough for external uses .

- updated default configuration values
- added an updated catalognumber property to the mediafile package.
  This will add two catalog numbers to the metadata.
- discogs_tagger will now conform to keep_original and embed_coverart
  property values
1.0.0
merging 1.0.0 branch.