/**
 * @param $tab
 * @return mixed
 */
function hwseo_get_tab($tab)
{
    return HWSEO_Setting_Tab::get_tab($tab);
}
 /**
  * @param $slug
  * @param $tab
  * @param $setting
  */
 public static final function init($slug, $tab, $setting)
 {
     $tab['slug'] = $slug;
     self::$setting = $setting;
     self::$setting_tab = $tab;
     add_action('load_' . $setting::PAGE_SLUG . '_' . $setting::valid_tab_slug($slug), get_called_class() . '::replyToAddFormElements');
 }