Record build success or failure on buildable objects
Summary:
Fixes T4810. When a buildable completes, make an effort to update the corresponding object with a success or failure message. Commits don't support this yet, but revisions do.
Test Plan:
- Used bin/harbormaster build and bin/harbormaster update to run a pile of builds.
- Tried good/bad builds.
- Sent some normal mail to make sure the mail reentrancy change didn't break stuff.
Reviewers: btrahan
Reviewed By: btrahan
Subscribers: epriestley
Maniphest Tasks: T4810
Differential Revision: https://secure.phabricator.com/D8803