Issue #86: Add ratings to shows/movies.

Added the ratings indicators to the movies.  This is a four star rating
due to space limitations on the screen currently.  The value retrieved from
plex is divided by 2.5 to obtain a rating that fits in the 4 star view.
Issue #86: Add TV Show Ratings

This adds TV show ratings based on the information from plex.
Add ROME library dependency.
Add model information for Music.

This starts to add the basic information that is needed to work with
Plex's and eventually Podcast audio files.