[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.
I'd rather have everyone working from a brew style recipe, and that's our plan anyway, to brew install the whole thing, in which case i would like to brew install python and whatever else we install.  otherwise it's a mess with different folks all reporting different bugs in the issues and we don't know what their setups are and we're asking things like "well type 'which python' please" -- standardizing on brew to install everything seems like a really reasonable thing to do imho