Add chat template

tokenizer_config.json

@@ -8,6 +8,7 @@
     ]
   },
   "bos_token": "<s>",
+  "chat_template": "{{ bos_token }}{% for message in messages %}{% if (message['role'] == 'user') != (loop.index0 % 2 == 0) %}{{ raise_exception('Conversation roles must alternate user/assistant/user/assistant/...') }}{% endif %}{% if loop.last and message['role'] != 'user' %}{{ raise_exception('Most recent message must come from user!') }}{% endif %}{% if message['role'] == 'user' %}{{ '<|User|>:' + message['content'] + '<eoh>\n'}}{% elif message['role'] == 'assistant' %}{{ '<|Bot|>:'  + message['content'] + '<eoa>\n'}}{% else %}{{ raise_exception('Only user and assistant roles are supported in this model!') }}{% endif %}{% endfor %}{{ '<|Bot|>:' }}",
   "clean_up_tokenization_spaces": false,
   "eos_token": "</s>",
   "use_fast": false,