add chat_template

tokenizer_config.json

@@ -14,5 +14,6 @@
   "padding_side": "left",
   "remove_space": false,
   "tokenizer_class": "ZhinaoTokenizer",
+  "chat_template": "{% for message in messages %}{% if loop.first and messages[0]['role'] != 'system' %}{{ '<|im_start|>system\nYou are a helpful assistant<|im_end|>\n' }}{% endif %}{{'<|im_start|>' + message['role'] + '\n' + message['content'] + '<|im_end|>' + '\n'}}{% endfor %}{% if add_generation_prompt %}{{ '<|im_start|>assistant\n' }}{% endif %}",
   "unk_token": "<unk>"
 }