Change from 13px to 11px

IMO, the font size feels cartoonishly large. @probablycorey will probably object. I know @kevinsawicki wanted to do this a while ago in the tree view.

From this:
![screen shot 2014-05-28 at 2 39 27 pm](https://cloud.githubusercontent.com/assets/69169/3111406/c59e47b4-e6b0-11e3-8a36-2b6ee498e352.png)

to this:
![screen shot 2014-05-28 at 2 38 43 pm](https://cloud.githubusercontent.com/assets/69169/3111409/cd619244-e6b0-11e3-9f04-ba95c1ec2f8e.png)