Cut down on rand dependency

[alexwennerberg]

Unless I am mistaken or don't understand the RFCs, message boundaries don't need high quality RNG. I believe you can replace with https://git.alexwennerberg.com/misc/file/rand.rs.html or a simpler non-cryptographic rng library

[mdecimus]

Thanks, I'll give it a try.

[mdecimus]

Just committed this fix. Ended up using a thread local counter combined with fibonacci hashing.

[alexwennerberg]

awesome! one more question, whats the reason for gethostname? could that part be dropped as well?

[mdecimus]

It's used to generate slightly more unique message IDs. However this could be moved as an optional dependency as the chances that two machines generate the same message Id at the same time are quite low.