Transformer base params for cifar-10.

def imagetransformer_base_imagenet_tpu():
  """Transformer base params for cifar-10."""
  hparams = imagetransformer_base_tpu()
  hparams.batch_size = 4
  hparams.num_heads = 4   # heads are expensive on tpu
  hparams.num_decoder_layers = 12
  hparams.block_length = 128
  hparams.layer_preprocess_sequence = "none"
  hparams.layer_postprocess_sequence = "dan"
  hparams.layer_prepostprocess_dropout = 0.1
  return hparams