Add D3 Factory, example directive for stat highlights #33

Not quite sure what the goal with the D3 charts should be. Added just a basic example of something we could do. Opening this up for discussion for different ways we could visualize this data.

![screen shot 2013-11-10 at 1 11 41 pm](https://f.cloud.github.com/assets/61091/1509479/354cd57c-4a4d-11e3-92df-3974159d3ec0.png)