changed:
 - common datatypes not directly included in xml schema language (File,
Collections) - in near future, probably all types will be moved into
this new namespace
 - the classes using bindings for external datatypes can specify use of
adapted classes with @XmlJavaTypeAdapter annotation, otherwise classes
directly derived of the schema will be used
 - UniMocker xml schema to import new common datatypes namespace and
schema for that namespace -> usage of new datatypes namespace in
UniMocker - still experimental