I've read that the big advantage of using btc casinos is that they are provably fair. Thanks to cryptography you can independently verify that you have not been cheated. That sounds great in theory but how do I go about putting a bitcoin casino to the test? Is this something only Peter Todd and Gregory Maxwell can do or is there a simple way that a non-techie person can check if the casino games they're playing are provably fair? Are all bitcoin casino provably fair or just some?