Migrate model card from transformers-repo

Read announcement at https://discuss.huggingface.co/t/announcement-all-model-cards-will-be-migrated-to-hf-co-model-repos/2755
Original file history: https://github.com/huggingface/transformers/commits/master/model_cards/google/bert2bert_L-24_wmt_en_de/README.md

README.md

@@ -0,0 +1,38 @@
+---
+language: 
+- en
+- de
+license: apache-2.0
+datasets:
+- wmt14
+tags:
+- translation
+---
+
+# bert2bert_L-24_wmt_en_de EncoderDecoder model
+
+The model was introduced in 
+[this paper](https://arxiv.org/abs/1907.12461) by Sascha Rothe, Shashi Narayan, Aliaksei Severyn and first released in [this repository](https://tfhub.dev/google/bertseq2seq/bert24_en_de/1). 
+
+The model is an encoder-decoder model that was initialized on the `bert-large` checkpoints for both the encoder 
+and decoder and fine-tuned on English to German translation on the WMT dataset, which is linked above.
+
+Disclaimer: The model card has been written by the Hugging Face team.
+
+## How to use
+
+You can use this model for translation, *e.g.*
+
+```python
+from transformers import AutoTokenizer, AutoModelForSeq2SeqLM
+
+tokenizer = AutoTokenizer.from_pretrained("google/bert2bert_L-24_wmt_en_de", pad_token="<pad>", eos_token="</s>", bos_token="<s>")
+model = AutoModelForSeq2SeqLM.from_pretrained("google/bert2bert_L-24_wmt_en_de")
+
+sentence = "Would you like to grab a coffee with me this week?"
+
+input_ids = tokenizer(sentence, return_tensors="pt", add_special_tokens=False).input_ids
+output_ids = model.generate(input_ids)[0]
+print(tokenizer.decode(output_ids, skip_special_tokens=True))
+# should output
+# Möchten Sie diese Woche einen Kaffee mit mir schnappen?