Depends on D20464. Ref T13277. Broadly:

• Move all the "should publish X" and "why aren't we publishing X" stuff to a separate class (PhabricatorRepositoryPublisher).
• Rename things to be more consistent with modern terminology ("Publish", "Permanent Refs").

This could use some trial-by-fire on secure, but:

• Grepped for all symbols.
• Viewed various commits.
• Reparsed commits.
• Here's a commit with an explanation: