- Minor bugs fixed
- semantics of include instruction changed -> the path of an included file is now relative to the metagrammar file dirname.

#  bug fixed in the XML output for Interaction Grammars
# bug fixed in the lexer (update of the filename(s) and line number(s) in case of recursive includes)
# modification allowing to import twice the same class (to avoid the tidious task of instanciating twice a class and dealing with id scopes)
# bug fixed in the processing of semantic information (constants were not allowed as predicate's arguments)
# bug fixed allowing the use of complex feature structures
# modification of the options of MetaTAG, --mac and --lin added for resp. extract sem macros and sem links (see doc)
# modification of the semantics of the include instruction, now included file path are given either relatively to the argument of MetaTAG / MetaIG or as absolute paths
# creation of module Preprocess.oz (formerly part of DisplayTrees) to be able to build semantic macros without loading Qtk