private static function copyBootstrap()
{
$bootStrapFolder = self::BOOTSTRAP_FOLDER;
$assetsFolder = self::getAssetsFolder();
if (!is_dir($bootStrapFolder)) {
throw new \Exception('can not find bootstrap folder');
}
if (!is_dir($assetsFolder)) {
throw new \Exception('can not find assets folder');
}
Helper::copy($bootStrapFolder, $assetsFolder);
}
