Fixed SOCKS handling, till now it was not possible to receive a packet from C unless you have sent to C in the past. Now C can initiate the connection if it knows your exit hop's address. This is implemented by claiming / reserving a circuit. All incoming packets will be forwarded to Swift. This also means that ProxyCommunity is no longer responsible for SELECTING ciruits, this is now done in Socks5Session.

 Will test this a few more times today, perhaps SEEDING after downloading will work now as well.