R1:38f2008e68b4

Modernize Diffusion lint controllers

Summary: Ref T4245. On their best day these don't work all that well, but I'm pretty sure I didn't make anything worse.

Test Plan:
- Viewed global lint.
- Viewed lint for a repository.
- Viewed lint details for a particular message.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T4245

Differential Revision: https://secure.phabricator.com/D14948