Adds "onRawEventUnmarshalled" can specify AMI Login Events param

* onRawEventUnmarshalled - returns a string containing the event received.  Useful for logging purposes or if your code wants to log events from various phone systems in a universal format.
* Login(..) now takes an events param which is sent as part of the login message.  This can be used to limit the types of events you receive.  For example, "call,hud" is good for retrieving just call events.