finally: packages to optionally create default collaboration dirs

["C. Gatzemeier" <c.gatzemeier@tu-bs.de>]

If collaboration among users should work nicely out of the box, we will
finally need three small things. I am not sure in which package some of
them should go, though.

1) An install? option to populate /etc/skel/ with the special permission
directories private/(rwx------) and incoming/ (rwsrws-wt)


2) An option for addgroup to automatically create groupdirs for
each created group: 

root:<group> (rwxrwsr-x) /home/group/<group>
root:<group> (rwxrws---) /home/group/<group>/private
root:<group> (rwsrws-wt) /home/group/<group>/incoming
http://bugs.debian.org/248130

3) A groupdir (like in 2) set up for the "users" system group.

But where/how should those things be created best?

Kind regards,
Christian