Add working protractor e2e test.

This uses the ignoreSynchronization flag because of the longpoll on the event
stream. It would be better to use $interval, but couldn't get that to
*reliably* work when testing. I suspect that $interval won't help us here,
since there is genuinely an open $http connection, as we're doing a long
poll. https://github.com/angular/protractor/issues/49 for more info.