R1:b056b7f174b5

Add edit notes to Phriction emails

Summary: Fixes T9294. Adds edit notes.

Test Plan: Edit a document, see notes in email.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: Korvin

Maniphest Tasks: T9294

Differential Revision: https://secure.phabricator.com/D16526