docs: protected HttpResponse sendPayload(HttpEntityEnclosingRequestBase request, byte[] payload, HttpHost proxy) {
      HttpResponse response = null;
      try {
        HttpClient httpclient = new DefaultHttpClient();
        if(proxy != null) {
          httpclient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, proxy);
        }
        request.setEntity(new ByteArrayEntity(payload));
        log(request);
        response = httpclient.execute(request);
      } catch(IOException ioe) {
        throw new EFhirClientException("Error sending HTTP Post/Put Payload", ioe);
      }
      return response;
    }