StandardBunch() doesn't use seed

[moellep]

The StandardBunch class doesn't use the seed arg if provided. One way to do this would be to use the seed to create a random instance, and then replace all the random.random() and self.np.random.randn() calls with self.random.random() and self.np_random.randn().

        if seed is not None:
            self.random = random.Random(seed)
            self.np_random = np.random.RandomState(seed)
        else:
            self.random = random
            self.np_random = np.random