Example of a simply UDP client

[elcritch]

Expanding on the selector method, I made a "wrapper" for tcp sockets, 
originally to help with multi-plexing serial/uart data on embedded /esp32. 
Async still gives me a headache so I like selectors. It should be very similar 
to UDP handling. 
<https://github.com/elcritch/nesper/blob/master/src/nesper/servers/tcpsocket.nim>