/// <summary>
        /// Retrieves a standard HTTP response header from a REST response, if available.
        /// </summary>
        /// <param name="response">The REST response.</param>
        /// <param name="header">The header to retrieve.</param>
        /// <param name="value">Returns the value for <paramref name="header"/>.</param>
        /// <returns><c>true</c> if the specified header is contained in <paramref name="response"/>, otherwise <c>false</c>.</returns>
        /// <exception cref="ArgumentNullException"><paramref name="response"/> is <c>null</c>.</exception>
        public static bool TryGetHeader(this Response response, HttpResponseHeader header, out string value)
        {
            if (response == null)
                throw new ArgumentNullException("response");

            if (response.Headers == null)
            {
                value = null;
                return false;
            }

            WebHeaderCollection collection = new RestWebHeaderCollection(response.Headers);
            value = collection[header];
            return value != null;
        }
        /// <summary>
        /// Retrieves a standard HTTP response header from a REST response, if available.
        /// </summary>
        /// <param name="response">The REST response.</param>
        /// <param name="header">The header to retrieve.</param>
        /// <param name="value">Returns the value for <paramref name="header"/>.</param>
        /// <returns><see langword="true"/> if the specified header is contained in <paramref name="response"/>, otherwise <see langword="false"/>.</returns>
        /// <exception cref="ArgumentNullException"><paramref name="response"/> is <see langword="null"/>.</exception>
        public static bool TryGetHeader(this Response response, HttpResponseHeader header, out string value)
        {
            if (response == null)
            {
                throw new ArgumentNullException("response");
            }

            if (response.Headers == null)
            {
                value = null;
                return(false);
            }

            WebHeaderCollection collection = new RestWebHeaderCollection(response.Headers);

            value = collection[header];
            return(value != null);
        }