public function addButton($content, $type = 'default', $properties = [])
    {
        if (isset($properties['class'])) {
            $properties['class'] = 'btn btn-'.$type.' '.$properties['class'];
        } else {
            $properties['class'] = 'btn btn-'.$type;
        }
        $button = new \Ease\Html\ButtonTag($content, $properties);
        return $this->addItem($button);
    }