added const_type: sg -> typ option; stamps now stored in REVERSE order; now supports 'draft signatures' and incremental extension: is_draft, add_classes (supports axclasses), add_defsort, add_types, add_tyabbrs, add_tyabbrs_i, add_arities, add_consts, add_consts_i, add_syntax, add_syntax_i, add_trfuns, add_trrules, add_name, make_draft; added const_of_class, class_of_const (for axclasses); changed the pure signature to support axclasses (added itself, TYPE); various major internal changes;

added print_sign, print_axioms: theory -> unit; replaced ["logic"] by logicS;

support for new style mixfix annotations; part of the pure syntax as mixfix (supports axclasses);