R1:31984a78eeeb

Add date to author panel in Maniphest

Summary: Adds a date with the author name on the Authored By panel in Maniphest. A basic treatment, will see how it feels.

Test Plan: Look at a few tasks

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: Korvin

Differential Revision: https://secure.phabricator.com/D15456