Add test for D<> plus L<defn:> case

Add test for D<> plus L<defn:> case.
Make CallbackAnchor for calling custom callback as Anchor

Make CallbackAnchor for calling custom callback as Anchor.
Fix Reformer.

In previous commit I move filter-args from Reformer method to Common sub.
Fix number of plan tests

Fix number of plan tests.
Implement reformer for case D<> with corresponding L<>

Implement reformer for case D<> with corresponding L<>.