Replace hand-rolled parentheses with the proper mdoc(7) macro, otherwise the closing ")" ends up inside the command description. Reported by Josh Rickmar, thanks!

Need for filtering by path sugggested by kn@ ok naddy@

positive feedback from Omar and kn ok kn

This has the advantage of tags being located right by the full command; combined with tags ":tco" to search for the `co` alias will jump right to the `checkout` line, neatly showing everything without needing further navigation. tmux hint from Thomas Adam, thanks. OK stsp

ok jrick