Little inconsistency in error messages, while validating JWTs

[prabath]

If the we directly hit a service with an expired JWT (before being added to the cache) - following is the error on the logs:

2018-10-31 06:08:46,174 DEBUG [ballerina/http] - Trying to authenticate with the auth provider: jwt-1
2018-10-31 06:08:46,348 ERROR [ballerina/http] - Error while validating JWT token : {message:"JWT token is expired", cause:null}

If the JWT is in the cache - and try the same (JWT) after it expires - I don't see any error logs.

2018-10-31 06:08:19,760 DEBUG [ballerina/http] - Trying to authenticate with the auth provider: jwt-1

[ldclakmal]

This is now fixed with the refactoring of the authn/authz framework [1] [2] for Ballerina 1.0. The inconsistency in error messages is also fixed along with that.

[1] #15056
[2] #15696