Support serializable for Diameter message

[duyanh030]

It is derived from ticket 34494.

When storing an object in CMP field. This object need to be implemented serialize/deserialized interface. This is the requirement in jain-slee spec 1.1

From SBB point of view. When receiving incoming event. I want to store it in CMP field and then it could be able to get back to create response later. Currently we can't do it by this way because most of our Diameter Request (CapabilitiesExchangeRequest, AccountingRequest, SessionRequest...) unable to serialize.

As a workaround solution now , When receiving a Request, I need to getAvps() -> from returned array get need information and put in CMP field. And create a response by
https://github.com/RestComm/jain-slee.diameter/blob/master/resources/diameter-base/common/ratype/src/main/java/net/java/slee/resource/diameter/base/DiameterMessageFactory.java#L68
It is not useful enough from customer point of view.

Or at least , We can support Diameter HEADER can be serialized, then SBB can use
https://github.com/RestComm/jain-slee.diameter/blob/master/resources/diameter-base/common/ratype/src/main/java/net/java/slee/resource/diameter/base/DiameterMessageFactory.java#L81

to create response

For more information please see 34494.