/**
  * Retrieves the singleton instance for this feature
  * @return AutomaticAssetsManager unique instance
  */
 public static function get_instance()
 {
     if (is_null(self::$instance)) {
         self::$instance = new self();
     }
     return self::$instance;
 }
 public function __construct()
 {
     $this->assets_manager = AutomaticAssetsManager::get_instance();
     $this->register_standard()->register_custom();
 }