Support a wider range of "Audit" rules for Owners packages

Summary:
Depends on D20124. Ref T13244. See PHI1055. Add a few more builtin audit behaviors to make Owners more flexible.

(At the upper end of flexibility you can trigger audits in a very granular way with Herald, but you tend to need to write one rule per Owners package, and providing a middle ground here has worked reasonably well for "review" rules so far.)

Test Plan:

• Edited a package to select the various different audit rules.
• Used bin/repository reparse --force --owners <commit> to trigger package audits under varied conditions.

Reviewers: amckinley

Reviewed By: amckinley

Maniphest Tasks: T13244

Differential Revision: https://secure.phabricator.com/D20126