Optionally allow the creation of a database column named 'active', so as to speed up state queries on larger datasets, and largely in support of changes in Eventful which now optionally can use that column when automating state changes.
Reworked the non-deterministic event ordering to use shuffled Array objects rather than Set, primarily because Ruby's Set seemed to be retaining order, which I'd assumed it wouldn't and that it would act much like a Ruby's old Hash in that regard.  I also added a global non-deterministic event ordering option on the stateful class method, which propagates that non-determinism to every state.