Implement CAS 3.0 Protocol (attributes exchange)
Seems People from JASIG have published specifications of CAS 3.0 protocol, see https://github.com/Jasig/cas/blob/master/cas-server-protocol/3.0/cas_protocol_3_0.md
Seems People from JASIG have published specifications of CAS 3.0 protocol, see https://github.com/Jasig/cas/blob/master/cas-server-protocol/3.0/cas_protocol_3_0.md