There are no longer distinct gendered versions of monsters, so femalenum
is unused (i.e. set to NON_PM) for all roles and races. Take a pass at
removing all uses of/references to femalenum, and rename 'malenum' to
'mnum' since it no longer has any particular association with
gender or sex.
If an old port is resurrected to work with current version code, its files
can be relocated to the appropriate sys or win folder as required.
In the meantime, the burden of upkeep can be avoided for the stuff in the
outdated folder for now.
