Minor feature release

• New Features

  • Add support for new user management features. Adds Client#query_role, Client#query_roles, Client#create_role, Client#drop_role, Client#grant_privileges, Client#revoke_privileges. Adds the 'Role' class. Adds UserRoles#read_info, UserRoles#write_info, UserRoles#conns_in_use to the UserRoles class.

• Improvements

  • Do not run PredExp tests for server v6+.