DEB_UNDIVERT_FILES should clean up .debathena conffiles

[geofft]

If you used to have DEB_DIVERT_FILES = a confflie, c-p-d should automatically remove that conffile if you set DEB_UNDIVERT_FILES to that conffile, since you don't still want it around.

You can use dpkg-query -W -f='${Conffiles}\n' | grep obsolete$ to look for symptoms of this. Examples I can find include /etc/gconf/2/path.debathena (undiverted in [r24993 debathena-gconf-config 1.7]), /etc/cups/cupsd.conf.debathena (undiverted in [r25317 debathena-cupsys-config 1.14]), /etc/apparmor.d/tunables/home.debathena, /etc/adduser.conf.linerva, and /etc/default/bitlbee.linerva (both undiverted in linerva-config 1.0.7).