Build heartbeat chain

MistoxServer/Server/ServerConnection.cs

@@ -26,7 +26,6 @@ namespace Mistox.Server {
             _client.NoDelay = true;
             _client.ReceiveTimeout = _parent.ConnectionTimeoutSeconds * 1000;
 
-            _parent.InvokeUserConnected( this );
             // Start the receive thread
             Task.Run(ReceiveThread);
         }
@@ -93,7 +92,6 @@ namespace Mistox.Server {
             _sendLock.Dispose();
             _cts.Dispose();
 
-            _parent.Connections.TryRemove(UserName, out _);
             _parent.InvokeUserDisconnected(this);
             // Remove this item from the Dictionary on the Server for garbage collection
         }