A version of this story first appeared in CNN Business’ Before the Bell newsletter. Not a subscriber? You can sign up right here. You can listen to an audio version of the newsletter by clicking the same link. New York CNN — Buying or selling a stock is about to get a lot snappier starting next Tuesday. But that doesn’t mean it’ll get smoother, at least right away — and some financial firms are preparing to handle any possible bumpiness. The current standard settlement cycle for broker-dealer tr...