code: protected HttpDelete createHttpDelete(String url, IGs2Credential credential, String service, String module, String function) {
  		Long timestamp = System.currentTimeMillis()/1000;
  		url = StringUtils.replace(url, "{service}", service);
  		url = StringUtils.replace(url, "{region}", region.getName());
  		HttpDelete delete = new HttpDelete(url);
  		delete.setHeader("Content-Type", "application/json");
  		credential.authorized(delete, service, module, function, timestamp);
  		return delete;
  	}
docs: DELETEリクエストを生成
  
  @param url アクセス先URL
  @param credential 認証情報
  @param service アクセス先サービス
  @param module アクセス先モジュール
  @param function アクセス先ファンクション
  @return リクエストオブジェクト