Add url-tab support part 1.

For the event details screen

1. selecting a tab now updates the url (meaning browser back and forward work)
2. the impact tab is auto selected if the event is completed
3. anything that can be deferred loaded is deferred loaded (not much really)
4. there is a slight speed up because some queries were parallelized
5. a bug was cleaned up that was causing spurious post requests (note that viewEvent has its own controller now).
6. a bug in ui-bootstrap v0.6.0 was fixed that had to do with initial tab activation. See http://stackoverflow.com/questions/17695629/setting-the-initial-static-tab-in-angular-bootstrap/19982402#comment29978056_19982402