Convert stray github urls into links in docs

Before:
![screen shot 2013-09-13 at 5 10 38 pm](https://f.cloud.github.com/assets/54056/1141673/53930680-1cb9-11e3-8cd5-8c43ee3d1a2d.png)

After:
![screen shot 2013-09-13 at 5 10 18 pm](https://f.cloud.github.com/assets/54056/1141672/5388af1e-1cb9-11e3-87dd-0b7605e711d4.png)