Allow addIdentityFields() to receive null as the identity. Will be needed for event-notifications.
Fix Notification.getOldObject()/Notification.getNewObject():
- Make them public so things such as the FCP interface can use them
- Throw the proper type of Exception
Change Notification.getOldObject()/.getNewObject() to return null instead of throwing:
- This is against the style convention we use in WOT but suitable because it will simplify the FCP code
- NoSuchElementException was not suitable anyway because it is a RuntimeException
Implement FCPInterface.sendIdentityChangedNotification