public string URLGetText(string url, TextParams parameters)
        {
            CheckURL(url);
            parameters.Url = url;

            return GET("URLGetText", "url", parameters);
        }
        public string HTMLGetText(string html, string url, TextParams parameters)
        {
            CheckHTML(html, url);
            parameters.Html = html;
            parameters.Url = url;

            return POST("HTMLGetText", "html", parameters);
        }