title: Can you specify an activity timeout for WebSocket4Net websocket
body: <p>Opened a WebSocket using a WebSocket4Net client against a relatively quiet server. After 4 minutes the socket is receiving a close message. After 4 minutes the socket is receiving a close message if no other message activity is received on the socket.</p>
  
  <p>Is there a timeout that is defined in the WebSocket? I'm trying to determine for certain that the WebSocket is closing from a timeout as the server has no activity timeout set so would allow the socket to remain connected indefinitely.</p>