(state_compare): Now inline. Return bool, not int.

(state_compare): Now inline.  Return bool, not int.
(state_comparator, stage_hasher): New function, to avoid casts.
(state_hash_new): Use new functions instead of casting old functions unportably.
(state_hash_lookup): Use MALLOC rather than alloca, so that we don't
have to worry about alloca.
(TRANSITIONS_ALLOC, ERRS_ALLOC, REDUCTIONS_ALLOC,
STATE_ALLOC): Remove.
(transitions_new, errs_new, reductions_new, state_new): Use malloc
rather than calloc, and use offsetof to avoid allocating slightly
too much storage.
(state_new): Initialize all members.
(state_hash): Use unsigned accumulator, not signed.