Added weak_eq_thm and forall_intr_vars (thanks to Mark Staples)
Added weak_eq_thm and forall_intr_vars (thanks to Mark Staples)

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