removed itlist, rev_itlist -- use fold_rev, fold instead; improved end_itlist;
removed itlist, rev_itlist -- use fold_rev, fold instead;
improved end_itlist;

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