Add swagger ui

I noticed that all of our `throws` statements are not being shown correctly in the docs UI. Can you have a look at fixing that as well?

![screen shot 2014-07-11 at 15 27 09](https://cloud.githubusercontent.com/assets/109850/3553814/7bb86dcc-0907-11e4-8d12-9160dea645b3.png)