Attribute revision promotion from "Draft" to "Needs Review" to the author
Ref T2543. When Harbormaster finishes builds and promotes a draft revision to review, we currently publish "Harbormaster requested review of...".
Instead, attribute this action to the author, since that's more natural and more useful.
Test Plan: Promoted a diff locally, saw it attributed to me rather than Harbormaster.
Reviewed By: amckinley
Maniphest Tasks: T2543
Differential Revision: https://secure.phabricator.com/D18730