static S uploadToImageServerIfNotThere(BufferedImage img, S name) {
  ret uploadToImageServerIfNotThere(null, img, name);
}

static S uploadToImageServerIfNotThere(File f, BufferedImage img, S name) {
  S md5 = md5OfRGBImage(new RGBImage(img));
  long id = imageServerCheckMD5(md5);
  if (id == 0)
    ret uploadToImageServer_new(f, img, name);
  else
    ret snippetImgLink(fsI(id));
}