If a registered sip client doesn't respond to OPTIONS requests , Restcomm should remove it about restcomm-connect

[gvagenas]

UserAgentManager stores the REGISTRATION object to the OPTIONS application session before send out.

UserAgentManagerProxy implements SipApplicationSessionListener, but when the OPTIONS request expires because there is no response, only SessionDestroyed event is fired and the
event.getApplicationSession().getAttribute(Registration.class.getName()) returns null.

[gvagenas]

There are cases where there is no Request Timeout for OPTIONS requests that don't get response.