pipeline PREPARE and EXECUTE

When server support it (mariadb 10.2+) and option pipeline is set (default) connection.execute first execution execute COM_STMT_PREPARE command and read COM_STMT_PREPARE result before executing COM_STMT_EXECUTE command.

Goal of this task is to pipeline COM_STMT_PREPARE and COM_STMT_EXECUTE like java connector does, to unnecessary wait for connector (if the rare case prepare fail, execute will return an additional error that will silently be discarded by connector