Sauce Integration 

Can someone review this, I haven't worked with `karma` before. Tests pass locally, but the sauce component is still untested.

Based the `karma.conf-sauce` file on [angularjs's karma sauce integration](https://github.com/angular/angular.js/blob/master/karma-shared.conf.js)

(BTW Sauce accounts are Jeremy's)
This gets out of my familiar zone, as I don't use Karma. I know on my own using Sauce I haven't had to deal with this. Seems very much a Karma specific thing.