Fatal error: Uncaught Error: Class 'yii\db\Migration' not found in /var/www/html/vendor/mdmsoft/yii2-admin/migrations/m140602_111327_create_menu_table.php:11 Stack trace: #0 {main} thrown in /var/www/html/vendor/mdmsoft/yii2-admin/migrations/m140602_111327_create_menu_table.php on line 11