* New Delegation Proof Type {DID, GENERIC}
* New API Proof objects: APIProof, APIDidDelegationProof, APIGenericDelegationProof used in advanced api
(decouple api from crypto proof, deal with deleagtion proof type and content, backward compatible)
* New Advanced API helpers to create generic proof and allow delegation with generic proof
* New validation mode according to the proof type
* New Regisered document delegation proof type serialization