Description: This worklog makes caching_sha2_password
             default authentication plugin for MySQL
             server and libmysqlclient.

             Worklog introduces 2 new options for
             CHANGE MASTER:
             1. master_public_key_path=<path> : Path
             to Master's RSA public key file
             2. get_master_public_key=1|0 : Preference
             to fetch RSA public key from master

             Further, group replication now supports
             two new options:
             1. group_replication_recovery_public_key_path=<path>
             Path to donor's RSA public key file
             2. group_replication_recovery_get_public_key=ON|OFF
             Preference to fetch RSA public key from donor

Reviewed-By: Kristofer Älvring <kristofer.pettersson@oracle.com>
Reviewed-By: João Gramacho <joao.gramacho@oracle.com>
Reviewed-By: Nuno Carvalho <nuno.carvalho@oracle.com>