Fatal error: Uncaught Error: Class "OCP\Migration\SimpleMigrationStep" not found in /home/tzuovhm/tzuovhm/core_/Migrations/Version14000Date20180516101403.php:12 Stack trace: #0 {main} thrown in /home/tzuovhm/tzuovhm/core_/Migrations/Version14000Date20180516101403.php on line 12