avoid double websocket-close message

IPython/frontend/html/notebook/static/js/kernel.js

@@ -98,7 +98,9 var IPython = (function (IPython) {
             " or if the url does not look right, there could be an error in the" +
             " server's configuration.";
         } else {
+            IPython.notification_widget.set_message('Reconnecting Websockets', 1000);
  	    this.start_channels();
+            return;
  	}
         var dialog = $('<div/>');
         dialog.html(msg);