Lingering edge cases:
	- User doesn't have hg, git, etc.
	- User has hg but not chg (fallback to hg)

Git support:
	- List untracked files @done
	- Determine based on presence of directory. @done

Niceties:
	- `--help` and `--version`
	- Maybe support choosing a directory instead of always using cwd?
	- Allow users to disable checks