Add required ID token fields: acr, amr, at_hash

[Tom Clancy]

See also Issue#37, which requires acr and amr values in ID tokens

[3.1] Required ID token fields: iss, aud, sub, vtm if vot is included, acr, amr, nonce, jti, auth_time. exp, iat, nbf, at_hash.

https://www.mitre.org/sites/default/files/2021-11/pr-19-3213-enterprise-tailored-oauth-profile.pdf

[3.1]

[Tom Clancy]

acr and amr addressed with vot/vtm in PR#17

[Kelley Burgin]

amr, acr included. Need to add at_hash