TCP listening added for IPv6 - New feature

[alan7000]

Hello,

Your implementation is pretty good, however for my use case, I mainly use IPv6 in my infrastructure.

Your implementation only uses IPv4.

netstat -an | grep 6556
tcp4 0 0 192.168.1.254.6556 192.168.1.251.33734 TIME_WAIT
tcp4 0 0 *.6556 *.* LISTEN 

On my side, I tried to add IPv6 listening but as I don't have enough experience in python, I didn't manage to finalize the IPv6 implementation.

Can you implement it?