Conpherence - make ZXXX monograms a bit more useful.

Summary: Ref T7756. Now viewing individual threads in Conpherence is ZXXX driven. Also adds remarkup support.

Test Plan: clicked around on list of conpherences in full view and it worked. selected 'view in conpherence' action from column and loaded correct ZXXX uri. Typed ZXXX in Maniphest and saw it link to Conpherence room.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: Korvin, epriestley

Maniphest Tasks: T7756

Differential Revision: https://secure.phabricator.com/D12397