BACM12 — The Owl ontology does not record abstract=True from the XMI

Abstract elements are not allowed to be instantiated. The MOF metamodel for BACM marks such elements as "abstract" but this information is not carried over to the Owl ontology, leading users to think that it is proper to "instance" (specialize) elements that should not be specialized directly; instead one of the concrete subclasses of the element should be used.

Add bacm_model:abstract owl:AnnotationProperty

Change BACMMOF2OWL.py make_class to determine if the isAbstract element is present with a value true. If so, generate an annotation property assertion in the class of bacm_model:abstract true . otherwise generate bacm_model:abstract false.