Setting pymc3 random seed at once

Could you file as a bug a short script that gets the wrong results? (or write it here and I can file)

Our intention is that you could set the random seed once anywhere - in a method call or not - and everything after would be deterministic. I think some of the variational inference API might not respect that yet, since it is using theano’s random number generator instead of numpy’s, but it would be good to enforce that rule.