Conpherence - add "room" search UI and create UI

Summary: Ref T7584. This hits all the major bullets there. Next step on T7584 is figuring out how it integrates into the full UI and column UI. That said, this is a bit buggy feeling right now since Conpherence as is assumes you are a participant all over the place and rooms make no such assumption. I'll probably this bit up next.

Test Plan:
viewed /conpherence/room/ and saw stuff. viewed the "participant" query as two different users and saw different correct result sets. made a room via the button and it worked. tried to view a room I wasn't a participant in and it failed horribly, which is something to fix in a future diff

created a thread via "send message" on a user profile and it worked

Reviewers: chad, epriestley

Reviewed By: epriestley

Subscribers: Korvin, epriestley

Maniphest Tasks: T7584

Differential Revision: https://secure.phabricator.com/D12113