Ref T13093. See PHI396. These are possibly somewhat niche, but reasonable to support and consistent with the existing "Pusher's projects".

Also relabel "Pusher's projects" and "Project tags" for consistency and, hopefully, clarity.

• Created new "commit" and "hook: commit content" Herald rules which run against "Author's projects" and "Committer's projects".
• Test console'd the "Commit" rules.
• Pushed through the "Hook" rule.
• In all cases, saw fields populate appropriately.