public static function build_signature($consumerSecret, $tokenSecret, $http_method, $Url, $oAuthOptions)
 {
     if (AppConfig::$debug) {
         print AppConfig::$lineBreak . '[------------------START DEBUG: SIGNATURE PARAMETERS--------------------]' . AppConfig::$lineBreak;
     }
     $base_string = RequestSigner::get_signature_base_string($http_method, $Url, $oAuthOptions);
     if (AppConfig::$debug) {
         print AppConfig::$lineBreak . 'BASE STRING: ' . $base_string . AppConfig::$lineBreak;
     }
     $key_parts = array($consumerSecret, $tokenSecret);
     $key_parts = Util::urlencode_rfc3986($key_parts);
     $key = implode('&', $key_parts);
     if (AppConfig::$debug) {
         print AppConfig::$lineBreak . '[------------------END DEBUG: SIGNATURE PARAMETERS--------------------]' . AppConfig::$lineBreak;
     }
     return base64_encode(hash_hmac('sha1', $base_string, $key, true));
 }