Description: This patch introduces atomicity
             in ACL DDL execution. It affects
             following DDLs:

             - CREATE USER [IF NOT EXISTS]
             - ALTER USER [IF EXISTS]
             - RENAME USER
             - DROP USER [IF EXISTS]
             - GRANT
             - REVOKE
             - CREATE ROLE [IF NOT EXISTS]
             - DROP ROLE [IF EXISTS]

Reviewed-by: Kristofer Pettersson <kristofer.pettersson@oracle.com>
Reviewed-by: Jon Olav Hauglid <jon.hauglid@oracle.com>
Reviewed-by: Andrei Elkin <andrei.elkin@oracle.com>