fr::HttpSocket has been removed.
fr::Sendable has been added. Classes can inherit this if they want to be sendable through sockets. Both fr::Http (which is inherited by fr::HttpRequest and fr::HttpResponse), and fr::Packet inherit this, to allow them to be sent through fr::Socket::send()/fr::Socket::receive().
Fixed broken fr::SocketSelector and fr::SocketReactor, as they no longer accepted fr::Listener's due to fr::Listener no longer inheriting fr::Socket.
Send/Recv often needs to be called multiple times to transfer all of the data. send_raw/receive_raw are now mutex protected and so both send & receive can be called simultaneously.
SocketReactor actually calls callbacks.
receive_all no longer tries to access out of bound array indexes.
fr::Packet constructor can now take as many arguments as you like and they'll be added to it automatically.
Added bool fr::Packet<< operator overload.
