Validate OIDC Access token with ZAAS Client

[balhar-jakub]

As a ZAAS client user, I want to validate OIDC access token in the same way as Zowe JWT. It is not possible to use /query endpoint for this. There could be a new method to validate OIDC access token and it should return username. It would be better to have 1 method and returned object would differ - contain mainframeID/distributedID.

String queryOIDC(String token);