The following changes were made to this otherwise pristine
/usr/lib references pointed at /usr/share, what
would have been /usr/lib/groff/font is /usr/share/groff_font.
tmac points at /usr/share/tmac (where bsd macro files go).
paths for cat[157] dirs added (BSD installs cattable files).
modified install_man/unintall_man target to install/deinstall
all mdoc files moved to the directory `notused'
and all references to them deleted from the
tmac.s moved to tmac.groff_ms (and ditto for tmac.an and
tmac.e) as bsd has its own and these check for
usage of groff versus troff.