postrm: Reconfigure a installed WM

After removal we need to make sure that at least any WM is configured.

DEBIAN/postrm

@@ -11,6 +11,14 @@ case "$1" in
                 db_purge
         fi
         rm -f /usr/sbin/kiosk-browser
+	# In a perfect world, this should also care for fvwm kdm lightdm xdm wdm slim lxdm gdm etc...
+	WMS=`dpkg-query -W -f='Package: ${Package}\nProvides: ${Provides}\n'   | grep -B 1 -E "^Provides: .*x-display-manager" | grep Package | cut -d" " -f2`
+	for I in $WMS
+	do
+		dpkg -l $I | tail -1 | grep ^ii > /dev/null && break
+	done
+	dpkg-reconfigure $I
+
 
     ;;
     *)