trippy related changes, some data format fixes

convlab/dst/trippy/__init__.py

convlab/dst/trippy/multiwoz/__init__.py

convlab/dst/trippy/multiwoz/__init__.py~

convlab/dst/trippy/multiwoz/modeling_bert_dst.prev.py

convlab/dst/trippy/multiwoz/modeling_bert_dst.py

convlab/dst/trippy/multiwoz/modeling_bert_dst.py~

convlab/dst/trippy/multiwoz/modeling_roberta_dst.prev.py

convlab/dst/trippy/multiwoz/modeling_roberta_dst.py

convlab/dst/trippy/multiwoz/modeling_roberta_dst.py~

convlab/dst/trippy/multiwoz/trippy.bck.py

convlab/dst/trippy/multiwoz/trippy.py

convlab/dst/trippy/multiwoz/trippy.py~

convlab/dst/trippy/multiwoz/trippypublic

convlab/dst/trippyr/__init__.py

convlab/dst/trippyr/multiwoz/__init__.py

convlab/dst/trippyr/multiwoz/modeling_roberta_dst.py

convlab/dst/trippyr/multiwoz/modeling_roberta_dst.py~

convlab/dst/trippyr/multiwoz/trippyr.py

convlab/dst/trippyr/multiwoz/trippyr.py~

convlab/evaluator/multiwoz_eval.py