Feature: Grouping Design (+ visual improvements and JSON display)

This includes a toggle for the grouping feature, the re-addition of the JSON display (which was somehow lost in branch history), and numerous visual improvements.

Screenshot:

![screen shot 2013-10-20 at 9 25 39 pm](https://f.cloud.github.com/assets/808159/1369908/0f372792-3a09-11e3-9132-0fd1529ff7e8.png)

/cc @thegoleffect