Deleted unused statistics

	modified:   ocaml/eiffelc.ml
	modified:   ocaml/support.ml
Preparation for interface verification

A module can be added as used module (in interface-use mode) or as
current module (in private mode).

The current module can be set from private mode to interface-check
mode.

	modified:   ocaml/class_table.ml
	modified:   ocaml/class_table.mli
	modified:   ocaml/context.ml
	modified:   ocaml/context.mli
	modified:   ocaml/eiffelc.ml
	modified:   ocaml/feature_table.ml
	modified:   ocaml/feature_table.mli
	modified:   ocaml/module_table.ml
	modified:   ocaml/module_table.mli