Fatal error: Uncaught Error: Class "yii\db\Migration" not found in /users/quirl/www/filemanager/spark/protected/humhub/migrations/m171015_155102_contentcontainer_module.php:5 Stack trace: #0 {main} thrown in /users/quirl/www/filemanager/spark/protected/humhub/migrations/m171015_155102_contentcontainer_module.php on line 5