a net.Conn compatible lib via QUIC

The initial code is cloned from quic-conn, but I refactored and updated codes to keepcompatible with latest https://github.com/lucas-clemente/quic-go.

Run the example

Start listening for an incoming QUIC connection

go run example/main.go -s

The server will echo every message received on the connection in uppercase.

Send a message on the QUIC connection:

go run example/main.go -c