code: protected void doPostMultipart(String path, InputStream inputStream) throws ClientException {
          doPostMultipart(path, inputStream, null);
      }
docs: Submits a multi-part form in an input stream. Adds appropriate Accepts
  and Content Type headers.
  
  @param path the the API to call.
  @param inputStream the multi-part form content.
  
  @throws ClientException if a status code other than 200 (OK) and 204 (No
  Content) is returned.