Multipane Preference Styling

1) Added the background styling (raised grey panel) to the preference panel on the right side
2) Added all of the margins and padding and other dimensions

See the example from Chrome, below:
![preference-multipane](https://f.cloud.github.com/assets/333672/144160/c76c5622-73f6-11e2-9fb0-ab1332ce7196.png)