Update Phurl to use EditEngine

Summary: Fixes T10673. Set up Phurl to use Edit Engine. There's no way this is all I needed to do to get it working, so I'll be making another pass at it and testing more thoroughly...

Test Plan: Ran through the Phurl URL creation/edit/deletion process.

Reviewers: #blessed_reviewers, epriestley

Reviewed By: #blessed_reviewers, epriestley

Subscribers: Korvin, epriestley, yelirekim

Maniphest Tasks: T10673

Differential Revision: https://secure.phabricator.com/D16573