HV-900 Documenting Java 8 support

> I think there is a miscommunication here. The type use validation is designed as part of the cascade routine. So @Valid must always be present to qualify the element as Cascadable. 

Right, we might have some miscommunication here. Explainable of course with all these discussion we had ;-) We will need to have another look at the code anyways after the latest discussions, so don't worry for now.

> his is to satisfy the requirement of only iterating once.

I don't think this should be related.