`turmoil::net::UdpSocket` is not API compatible with `tokio::net::UdpSocket`

[howderek]

I am trying to use turmoil to simulate a UDP load balancer, but I am not able to use turmoil::net::UdpSocket instead of tokio::net::UdpSocket without rewriting components of the load balancer.

Two issues I have run into so far is turmoil::net::UdpSocket::send is private and turmoil::net::UdpSocket::connect does not exist, while in tokio::net::UdpSocket, connect and send are both public methods of UdpSocket.

[mcches]

These still need to be implemented. UDP hasn't been as prioritized as TCP. You are welcome to pick up this work and submit a PR for the methods you need.