Piwik\Widget\WidgetConfig::setOrder PHP Method

    public function setOrder($order)
    {
        $this->order = (int) $order;
        return $this;
    }

 public static function configure(WidgetConfig $config)
 {
     $config->setCategoryId('About Piwik');
     $config->setName('Installation_SystemCheck');
     $config->setOrder(16);
     $config->setIsEnabled(Piwik::hasUserSuperUserAccess());
 }