Added ID column to games list

Quite simply added a column labeled "ID" to the main games list.  Personally, when I ripped my games, they ripped as <ID>.iso.  It's much easier to match them up with their files it the id is displayed.  
![dolphinidcol](https://cloud.githubusercontent.com/assets/3501739/3085631/61045fc8-e516-11e3-9c1b-e3f0e43e22b3.png)