moved helper lemma to HilbertChoice.thy; use actual ObjectLogic.atomize_cterm; eliminated obsolete sign_of;
moved helper lemma to HilbertChoice.thy;
use actual ObjectLogic.atomize_cterm;
eliminated obsolete sign_of;

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