test(multi): added Internet Explorer 11 to ciConf.js (SauceLabs)

I think we should be testing protractor against IE for every change since [it's still a very active browser](http://gs.statcounter.com/#browser-ww-monthly-201404-201412-bar) and I also think IE11 is a good start since is a modern browser that auto-updates plus [angular 2.0 will support it](http://blog.angularjs.org/2014/03/angular-20.html)

Side note, running `npm test` against IE11 allowed me to confirm an issue I was having previously: https://github.com/angular/protractor/issues/778