Change to not install catman pages & single user

[David Brownlee <abs%absd.org@localhost>]

Last week I had cause to lookup a manpage in single user on a netbsd-6 BETA box.

Since the change to not install catman pages this currently requires
creating a temporary file before formatting for display.

Unfortunately the system was panicing when / was mounted r/w - in the
end I mounted a tmpfs on /tmp to continue, an alternative would be to
run mandoc /usr/share/man/... | less.

Should man(1) be handling this automatically? does it really need to
save its output to a temporary file?