Added
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- added Dockerfile for rasa\_core\_sdk
- add `active_form` and `latest_action_name` properties to `Tracker`
- add `FormAction.slot_mapping()` method to specify the mapping between
user input and requested slot in the form
- add helper methods `FormAction.from_entity(...)`,
`FormAction.from_intent(...)` and `FormAction.from_text(...)`
- add `FormAction.validate(...)` method to validate user input
Changed
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- `FormAction` class was completely refactored
- `required_fields()` is changed to `required_slots(tracker)`
- moved `FormAction.get_other_slots(...)` functionality to
`FormAction.extract_other_slots(...)`
- moved `FormAction.get_requested_slot(...)` functionality to
`FormAction.extract_requested_slot(...)`
- logic of requesting next slot can be customized in
`FormAction.request_next_slot(...)` method
Removed
=======
- `FormField` class and its subclasses
Fixed
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