Added initial styling to leaderboard

![screen shot 2014-08-05 at 1 19 53 pm](https://cloud.githubusercontent.com/assets/7501476/3815423/c2143af0-1cc4-11e4-80b9-73cccb296a3d.png)
An initial pass at the leaderboard.  I will need to talk to someone in UX about it, but this sets up a basic structure that will be easy to edit (and much more pleasing to look at)