Fatal error: Uncaught Error: Class "Concrete\Core\Block\BlockController" not found in /srv/disk1/2895578/www/whittonphotographicclub.org.uk/concrete/blocks/image_slider/controller.php:16 Stack trace: #0 {main} thrown in /srv/disk1/2895578/www/whittonphotographicclub.org.uk/concrete/blocks/image_slider/controller.php on line 16