Portoption #105

Sorry to resubmit this, I spent some more time testing and messed up my repo. In any case there are no changes from the original. Just gavin's portoption and the removal of the 2h penalty for non-standard port clients.

Given that -port is oft-requested and oft-implemented, and a standard option on other servers, I think we should include that.

However, I am not sure we should be removing penalties until things like ensuring diversity of incoming connections is handled.

Phantomcircuit started a topic on the forum to discuss Sybil attacks and what, exactly, we should to to prevent them (http://www.bitcoin.org/smf/index.php?topic=4335.0). I would, however, like to point out that the penalties removed here have nothing to do with incoming connections and the penalties here are really unnecessary as the client only makes one outbound connection per /16.

After the discussion on IRC and a bit of soul searching, I came to the conclusion that having a -port option is bad for the overall network. The problem rests with the ability of people to more easily run multiple nodes on the network. This should be discouraged as it increases load on IRC, etc. Anyone who has enough ability to want an alternate port for whatever reason can easily do this with firewall rules or with a compilation with the above commits.