adds functions returning number of expected (|remaining|fed|bound) args

closes Ticket #2867 (feature request)

[SVN r57734]

libs/format

@@ -1 +1 @@
-Subproject commit a995d9ca4eb9f74cb6d8b96b2059c291c1c8ec6b
+Subproject commit a6403171c04fa917e09473ac2ccc154e0cae4fd0