Second attempt at XBMC MySQL support 

Added the ability to use a centralized MySQL XBMC library database. 

As of the right now, if the connection fails, the user will not be alerted.  If the movie already exists in the library, the user won't be alerted and the movie won't be added to the queue.  

I have kept the ability to check in either the SQLite local database or connect to a MySQL server hosted library.  The setup can be found on the Extras tab, as I did not feel it made sense for this to be under Notifications.