nonce field

[1001bug]

additional claim - check nonce field
Google Api allow to use it, would be perfect to automate test on it

iss, sub, aud, jti

218 foreach my $claim (qw(iss sub aud jti nonce)) <--- add nonce to use as verify_nonce

[karel-m]

nonce is not a Registered claims according JWT specification

There is a bunch of other public claims e.g. https://www.iana.org/assignments/jwt/jwt.xhtml#claims (I do not think that library like Crypt::JWT should check these; if nonce why not others)