Hide uninstalled applications on the "Home Application Tiles" preferences page

Summary: Fixes T4685.

Test Plan: loaded home page settings and saw phrequent, uninstalled phrequent, refreshed, and no longer saw phrequent!

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: epriestley, Korvin

Maniphest Tasks: T4685

Differential Revision: https://secure.phabricator.com/D8640
Fix an issue where email for "accepted" revisions would fatal

Summary: When trying to render "BRANCH", we need the active diff. Load it
in general since it seems reasonable for custom fields to expect it to
exist during mail rendering.
Fix maniphest "create" transactions

Summary: the quotes are 'cuz "create" is inferred. Previously, we inferred on "status", but since we set that on "initializeNewTask" instead infer off "title" (aka "name") like most other apps do. Only hairy tweak was to elevate TYPE_TITLE to the most important of all maniphest transactions, which doesn't actually seem too unreasonable if not correct even? Fixes T4686.

Test Plan: made a new task, used bin/mail, got the right headers (mail vary prefix == created)

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: epriestley, Korvin

Maniphest Tasks: T4686

Differential Revision: https://secure.phabricator.com/D8639