Unify naming of base,root image settings

testing/start-testing

@@ -22,7 +22,7 @@ done
 
 for host in $STRONGSWANHOSTS
 do
-	ln -fs $ROOTFSDIR/$host.qcow2 $VIRTIMGSTORE/$host.qcow2
+	ln -fs $GUESTIMGDIR/$host.$IMGEXT $VIRTIMGSTORE/$host.$IMGEXT
 	log_action "Guest $host"
 	execute "virsh create $CONFDIR/$host.xml"
 done