fixup! BB 41803: Add some developer tools for working on tor-browser.

TB 44367: Improve the auto-fixup/auto-commit command.

The auto-fixup command was renamed to auto-commit. It now also handles:

1. Already staged changes.
2. Untracked/added files.
3. Removed files.
4. Renamed files.
5. Allowing the user to create a new commit.