Rewrite to use a static class

An API client should be a simple program to abstract the API to native objects.  This is what I've done with the Gracenote API.  The library is written in PSR-0 format so it can be included with the PHP package manager Composer.  

Additional steps needed when this commit is merged
1. Rename your repo from php-gracenote to GracenoteClient-PHP
2. Edit composer.json and change the name from "gracenote/gracenote-tha" to "gracenote/gracenote"
3. Add a license.  I hold no claim to this project but request my name remain in the composer.json as the author.
4. Add the project to packagist.org 
5. Update this pull request when 1-4 are done.