Sequential server class.
This class will handles all connection in one server process.  This allows you to build servers, where communication between  the clients is easy. The drawback is that clients are served  sequentially (hence the name). If you send large blocks of data  to a client, the others will have to wait.  For servers where communication between clients is not needed,  use Net_Server_Fork instead.
Events that can be handled: 
onStart
onConnect
onConnectionRefused
onClose
onReceiveData
onShutdown