Check if the user can open a port and connect to it

Somewhere in the first run wizard, there should be a way that the user can attempt to start a server on the c6 port (not the cryptic6 server, though) and either attempt to connect to it themselves using the outside IP that they provided, or have another server try to connect to it. If it fails, it should warn the user that cryptic6 won't work on their computer until they fix their network settings.