Use terminfo colors as defaults instead of hard-coded values

[foltik]

Perhaps the man colors could default to the terminal's default colors using tput(1) as described in https://unix.stackexchange.com/a/147. I'd guess most users already have terminal colors configured elsewhere, so this would reduce the need for manual configuration. Users could still override these colors if needed.

Willing to submit a PR if you're open to it!

[miyl]

Good suggestion! Feel very free to submit it to my fork:
https://github.com/miyl/fish-colored-man

I merged in the open PR to this repo to that fork as well.
I don't have any particular wishes to maintain it, though, so maybe submit it here too in case @decors sees it.