Support for COSE Key encoding

[pkbharigopal]

FIDO UAF 1.1 specification (https://fidoalliance.org/specs/fido-v2.0-rd-20180702/fido-registry-v2.0-rd-20180702.html) recommends the EdDSA keys to be encoded as per COSE specification as defined in Section 7 of https://tools.ietf.org/html/rfc8152#section-7 . Can someone guide on how to achieve this. Essentially, the getEncoded() on the EdDSAPublicKey object should return the keys in COSE format, and similarly one should be able to construct EdDSAPublicKey object from key bytes [] defined in COSE. Any help is highly appreciated.