====== onIncompatibleVersion() ======
wrtc.onIncompatibleVersion() is an event function called when when client and IXNX server use incompatible protocols. As they cannot communicate with each other further operation is impossible.

You can use this event to prompt user to update to latest version.

===== Occurs =====
If client and IXNX server use different protocol version numbers on RTCgate websocket connection.

===== Arguments =====
wrtc.onIncompatibleVersion(obj, arg)
  * obj - socket object raising the event
  * arg - JSON structure {currentVersion:..., serverVersion:...}
    * currentVersion - RTCgate version this client is using
    * serverVersion - RTCgate version server is using

===== Return value =====
Ignored.