RuleCases.make_common/nested;

* Provers/induct: improved simultaneous goals -- nested cases;

added private datatype nprod (copy of prod) to be used in the induction rule

changed PRO_RED proof to conform with the new induction rules

prep_meta_eq: reuse mk_rews of local simpset; adapted ML code to common conventions; tuned;

removed obsolete eqrule_HOL_data.ML;

removed obsolete eqrule_FOL_data.ML;

simplified EqSubst setup;

obsolete, reuse mk_rews of local simpset;

Toplevel.theory_to_proof;

transactions now always see quasi-functional intermediate checkpoint; removed obsolete theory_theory_to_proof; added

tuned EqSubst setup;

Pure/Isar: Toplevel.theory_to_proof admits transactions that modify the theory;

hide type datatype node; added theory_node, proof_node, is_theory, is_proof, proof_position_of, checkpoint, copy; no_body_context: no history; transaction: test save = true;

tuned print_theorems_theory;

Toplevel.proof_position_of;

store_thm: transfer to current context, i.e. the target theory;

replaced swap by contrapos_np;

added setminus; tuned;

proper handling of simultaneous goals and mutual rules;

provide projections of induct_weak, induct_unsafe;

added strict_mutual_rule;

RuleCases.strict_mutual_rule; export internalize;

changed the name of the type "nOption" to "noption".

added "fresh_singleton" lemma

added more documentation; will now try out a modification of the ok-predicate

Reversed Larry's option/iff change.

substantial additions using locales

exported read|cert_arity interfaces

trace_simp_depth_limit is 1 by default

removed pointless trace msg.

preservation of names