R1:4307d6816d30

Linkify Registration Email

Summary: Missed this in previous pass. Send these as links in HTML emails.

Test Plan: Register a new user that nees approval.

Reviewers: btrahan, epriestley

Reviewed By: epriestley

Subscribers: Korvin, epriestley

Differential Revision: https://secure.phabricator.com/D10815