Switch default port to something other than `80`

[mellonnen]

When I try to run the rendezvous server locally I get this error,

as port 80 is a privileged port and therefore a non-root process cannot use it.

Do not know if it is my setup or whatever but we should probably change it?

[ZinoKader]

Yes, the default should be some ephemeral TCP port, not 80 which is HTTP. How about 65432?

[mellonnen]

Also, it does not really make sense for the sender/receiver to have to provide IP and port individually. In the case, you want to send through a self-hosted rendezvous server you would have to provide both. We should probably accommodate both the Sender and Receiver stucts to accept an option for IP and port , and join the port and address cli flags into one flag.

---

edit: we could create an option

WithRendevouzTCPAddr(add net.TCPAddr)

for the Sender and Receiver structs, which logically makes more sense then providing port/address in two different options