[Feature] unify da representations of different datasets

[zqwerty]

Describe the feature Unify different dialogue act representation of different datasets to: (intent, domain, slot, value)

Expected behavior change dialogue act usage in (multiwoz, camrest) X (nlu, nlg, dst, policy)

Additional context Add any other context about the feature here.

[zqwerty]

file to change:

• tatk/util
  • [x] multiwoz/lexicalize.py
  • [x] multiwoz/state.py
  • [x] multiwoz/dbquery.py
  • [x] camrest/lexicalize.py
  • [x] camrest/state.py
  • [x] camrest/dbquery.py