to the debug callback.

- Shmulik Regev added CURLOPT_HTTP_CONTENT_DECODING and
  CURLOPT_HTTP_TRANSFER_DECODING that if set to zero will disable libcurl's
  internal decoding of content or transfer encoded content. This may be
  preferable in cases where you use libcurl for proxy purposes or similar. The
  command line tool got a --raw option to disable both at once.