Merge pull request #122 from ConvLab/crossowoz_ddpt

convlab/policy/vector/vector_base.py

convlab/policy/vector/vector_nodes.py

convlab/policy/vector/vector_uncertainty.py

convlab/policy/vtrace_DPT/create_descriptions.py

...ab/policy/vtrace_DPT/transformer_model/action_embedder.py

...ace_DPT/transformer_model/action_embeddings_multiwoz21.pt

...ransformer_model/embedded_descriptions_base_multiwoz21.pt

...e_DPT/transformer_model/small_action_dict_multiwoz21.json

convlab/util/multiwoz/lexicalize.py