add_axiom: axiomatize "unconstrained" version, with explicit of_class premises; more uniform add_axiom/add_def;
add_axiom: axiomatize "unconstrained" version, with explicit of_class premises;
more uniform add_axiom/add_def;

MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle