[Add WACI protocol support for didcomm v2]

[AlexAndrei98]

Exchanging credential with didcomm is a basic use case that an agent should have.
I propose adding support for basic issuance and verification purposes.

The underlying protocols to exchange credentials are based on Aries RFC0453 and 0454 with the addition of credential manifest and presentation exchange objects

Useful Links
WACI-DIDComm Spec
Go protocols implementation

[nickreynolds]

would it be possible to break this into multiple issues? for one, I think the QR-code work could be separated from the rest of it?

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.