Run Selenium tests on Sauce 

Firefox on Linux for now (the default). Will add others as we get them working.

[![Woo hoo!](http://img.youtube.com/vi/SSbBvKaM6sk/0.jpg)](http://www.youtube.com/watch?v=SSbBvKaM6sk)

![](http://i.imgur.com/JKTF9GJ.gif)