stop majordomo from chowning /var/tmp to user majordom due to a superannuated
default in mk/defaults/mk.conf

remove the non-shared defaults and put in the setting that actually gets
used by more than one package (namely, MAJORDOMO_HOMEDIR)

don't make the majordom user own more than it actually needs to

make resend, archive, request-answer and medit honor the MAJORDOMO_CF
environment variable over the command line option, so that someone calling
these via the wrapper (which sets the environment variable) can't make
the majordom user execute random perl code by specifying it as config file.
Thanks to salo for finding this issue.

(spz)