Updates and fixes

Added

• #54 New Unit test
• #73 New claims for user
• getUsername() is preferred_username or null
• getFirstName() is given_name or null
• getLastName() is family_name or null

Deprecated

• nothing

Fixed

• #53 IdentityProviderException return error code except only zero (closing #36, #73)

Removed

• nothing

Security

• Allowed JWT version 6 only, due to CVE in older versions