Create a modal for "Contact Us" that includes mailing address & email address

Previous behavior: 

- Contact Us was a `mailto` link to info@

New behavior:

![screen shot 2013-12-10 at 4 41 56 pm](https://f.cloud.github.com/assets/1319950/1714393/de28fb3e-61a0-11e3-88eb-af4b05ba5904.png)

Solves #18