Merge pull request #45 from ConvLab/nlg-scgpt

convlab2/nlg/scgpt/README.md

convlab2/nlg/scgpt/decode.py

convlab2/nlg/scgpt/evaluate.py

convlab2/nlg/scgpt/main.py

convlab2/nlg/scgpt/model.py

convlab2/nlg/scgpt/modeling_utils.py

convlab2/nlg/scgpt/scgpt.py

convlab2/nlg/scgpt/scgpt_special_tokens.py

convlab2/nlg/scgpt/test.sh

convlab2/nlg/scgpt/train.py

convlab2/nlg/scgpt/train.sh

convlab2/nlg/scgpt/util.py