Added some more comments

	modified:   ocaml/feature_table.ml
Added function to recalculate class map and feature map

... for interface-check mode

	modified:   ocaml/class_table.ml
	modified:   ocaml/feature_table.ml
Fix: Set filename so that the errormessage displays the proper file

	modified:   ocaml/eiffelc.ml
More preparations to verify interface files

	modified:   ocaml/class_table.ml
	modified:   ocaml/class_table.mli
	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
	modified:   ocaml/proof_context.ml
	modified:   ocaml/proof_context.mli
	modified:   ocaml/proof_table.ml
	modified:   ocaml/proof_table.mli
Decoupled public and private view in class table

The public and private view in the class table are now completely
decoupled. This applies to classes to features and assertions of
classes and to descendants and ancestors.

Each addition/modification made in the private view is accessible
only in the private view, each addition/modification made in the
public view is available in both views.

Builtin classes are inserted only to the private view. The same
applies to builtin functions.

The same decoupling still has to be done for the feature table as
well in order to be able to verify interface files.

	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/proof_context.ml
	modified:   ocaml/proof_context.mli
Verification of interface files activated

The verification works on some standard examples. However the decoupling
of private and public view in the feature table is not yet done completely
and therefore there is still some work to be done to complete the
verification of interface files.

	modified:   ocaml/class_table.ml
	modified:   ocaml/class_table.mli
	modified:   ocaml/eiffelc.ml
	modified:   ocaml/feature_table.ml
Decoupled private and public view in feature table

Each inheritance done in the private view is available only in the
private view. Each inheritance done in the public view is available
in both views.

Builtin functions (except 'all' and 'some') are by default available
only in the private view unless explicitely exported.

	modified:   ocaml/feature_table.ml
	modified:   ocaml/proof_context.ml
Some cleanups in the parser and the lexer

The module Support.Parse_info is no longer necessary to process error
messages during parsing and lexing.

The lexer calls 'error_info' directly because it has all position
in case of a lexing error.

The parser just raises 'Parsing.Parse_error' and the handler gets the
position of the last token (the unexpected token) from the lexer.

	modified:   ocaml/eiffelc.ml
	modified:   ocaml/lexer.mll
	modified:   ocaml/parser.mly
	modified:   ocaml/support.ml