Big Button for Buying Tickets

* added big button for buying tickets.
* added Digital Ocean to list of sponsors.
* added actual location of venue.

![screen shot 2014-09-15 at 11 38 35 pm](https://cloud.githubusercontent.com/assets/194609/4283325/9a766194-3d6c-11e4-8874-2431fc32043d.png)