R1:1a3bf098ae4a

Correctly parse author and committer identities again

Summary: See D3977, a terrible diff where I made a huge messs.

Test Plan: Ran `reparse.php --message --trace <revision>`, verified correct identification of author.

Reviewers: edward, vrana

Reviewed By: edward

CC: aran

Differential Revision: https://secure.phabricator.com/D4104