Fatal error: Uncaught Error: Class "OCP\Migration\SimpleMigrationStep" not found in /home/tzuovhm/tzuovhm/nextcloud/core/Migrations/Version17000Date20190514105811.php:17 Stack trace: #0 {main} thrown in /home/tzuovhm/tzuovhm/nextcloud/core/Migrations/Version17000Date20190514105811.php on line 17