Include underscore library.
Clients now have a numerical ID.
Server can now clean up client list when removing a client.
Added writeBool(), writeInt(), writeDouble() and writeFloat(). Removed some logging.
Packet doesn't need an ID field specified in format, all packets have this by default.
Support additional packets.
Cleaned up logging and packet writing routine.
Added respawn(), completeLogin() and sendSpawnPosition().
Client based responders must be bound later, so defer these until the packet arrives.
Added support for additional types.