Ratings gui

I have merged the original Ratings GUI resources and code from the traktr addon into the official branch, and updated everything to work with XBMC Frodo. Needs testing, but episode, tvshow and movie rating all work from my Frodo installation.

![RateMovieGUI](https://f.cloud.github.com/assets/2003744/122009/3e21785c-6e1f-11e2-9a4b-4825d08e28f8.png)