Prepare UserPreferences for transactions
Summary:
Ref T4103. This give preferences a PHID, policy/transaction interfaces, a transaction table, and a Query class.
This doesn't actually change how they're edited, yet.
Test Plan:
- Ran migrations.
- Inspected database for date created, date modified, PHIDs.
- Changed some of my preferences.
- Deleted a user's preferences, verified they reset properly.
- Set some preferences as a new user, got a new row.
- Destroyed a user, verified their preferences were destroyed.
- Sent Conpherence messages.
- Send mail.
- Tried to edit another user's settings.
- Tried to edit a bot's settings as a non-admin.
- Edited a bot's settings as an admin (technically, none of the editable settings are actually stored in the settings table, currently).
Reviewers: chad
Reviewed By: chad
Maniphest Tasks: T4103
Differential Revision: https://secure.phabricator.com/D15991