Add TokenStore supporting JWT verification using JWK

[jgrandja]

It would be very useful to have a TokenStore implementation that verifies a JWT using a JSON Web Key (JWK).

The main goal of this implementation would be to verify a JWT using the corresponding JWK. The JWK used for verification is matched using the kid header parameter of the JWT and the kid attribute of the JWK.

The implementation would be responsible for fetching the JWK Set (the set of available JSON Web Key's) from the supplied URL.

Related Specifications

JSON Web Token (JWT)

JSON Web Key (JWK)

JSON Web Signature (JWS)

JSON Web Encryption (JWE)

JSON Web Algorithms (JWA)