Update Rand version

[dhardy]

Regex currently requires Rand ^0.4. Given the extremely limited use by this library, you could probably get away with >= 0.3; I think at least >= 0.3 < 0.7 should be safe.

[dhardy]

Sorry, incorrect. But if you replace:

                let numbers: Vec<$numty> =
                    rand::thread_rng().gen_iter().take(100000).collect();

with

   let mut rng = thread_rng();
   let numbers: Vec<$numty> = (0..100000).map(|_| rng.gen()).collect();

you should have no problems. See rust-random/rand#286