randaut: -S should mean --state-based-acceptance

Currently in randaut, -S is used to select the number of states, but everywhere else (except randltl) -S is used for --state-based-acceptance (a.k.a., --sbacc).

We should rename the actual -S to something like -N or -Q, and also rename --state-acc to support --state-based-acceptance and --sbacc.