Move DMPPluginAttribute into the DarkMultiPlayerServer namespace, and only allow usage on classes.
Move CONNECTION_END termination after EndWrite.
Disconnect clients when they send a connection end message.
Added DMPPlugin base class with virtual methods
Killed delegates and attributes with fire. Implemented plugins using interfaces.
Killed OnMessageReceivedRaw with fire. Now plugins can set ClientMessage.handled = true to suppress DMP processing of that message.
Improve vessel positioning
Reduce vessel updated in future timeout
Give hacky-vessel-load a longer timeout
Initial 0.24 support