[WIP] update mac configure script and add messaging about common port forwarding issue

update mac configure script and add messaging about port forwarding until we maybe use a better solution like how libtorrent does this, or RPC & UDP like this https://github.com/bmuller/rpcudp to avoid most port forwarding issues.
hopefully one day the project is just an app people install and they aren't ever worried about configuring stuff.  no one is worried about getting utorrent working.  the app just works. i don't think it's a good use of time to worry about this stuff.   for now, getting all mac users on a consistent environment so we can debug real issues (a lot of issues i've seen in the past were people who just had misconfigured systems, they would paste really long output from configure.sh and it's not a good use of *anyones* time to go through that -- neither the user nor us)