WIP Overhaul view and sort behavior

Big changes to view, sort, routing, filtering, etc, etc, etc...

Todo
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- [x] stream search -- race between $scope.updater and stream controller, need to send the filter
- [x] page search -- simple matter of fixing the ugly ng-show conditions at the bottom of the viewer template perhaps with more verbose, obvious variables, or scope/controller functions to abstract the route details from the template a bit
- [x] Check on https://github.com/hypothesis/h/pull/1436#discussion_r16705832 (leave as is 2014-08-29)
- [x] Restore "no results for “query”" message.
- [x] Annotations don't watch for changes
- [x] forced login -- a comment about ideas for that [here](https://github.com/hypothesis/h/issues/1020#issuecomment-53400218)
- [ ] Card emphasis on highlight hover
- [ ] Redaction

Yes, it's fine. We no longer attach things manually but use the full threading algorithm whenever load occurs. That algorithm creates any reference containers that are missing for each message, which means the parent container for a reply is initialized and empty if the reply is processed first and then the parent is filled in later.