More restrictive cleanup

backup.sh

@@ -16,7 +16,7 @@ exit_on_fail(){
 retrie_on_fail(){
     if [ $1 -ne 0 ]; then
         backup "cleaned"
-        run_duplicity remove-all-inc-of-but-n-full 1 --force
+        run_duplicity remove-all-inc-of-but-n-full $(($BK_KEEP_FULL-1)) --force
         leave $?
     fi
 }