readme: Converted for Tensorflow
  ```
  !pip install transformers sentencepiece
  from transformers import TFAutoModel, AutoTokenizer
  name = "xlm-roberta-base"
  model = TFAutoModel.from_pretrained(name, from_pt=True)
  tokenizer = AutoTokenizer.from_pretrained(name)
  model.save_pretrained("local-xlm-roberta-base")
  tokenizer.save_pretrained("local-xlm-roberta-base")
  ```