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- Drop/merge `flask_restful.Resource` resolving a recursion problem
- Allow any `callable` as field `default`, `min`, `max`...
- Added :class:`~fields.Date` field
- Improve error handling for inconsistent masks
- Handle model level default mask
- support colons and dashes in mask field names
- **Breaking changes**:
- Renamed `exceptions` module into `errors`
- Renamed `RestException` into :class:`~errors.RestError`
- Renamed `MarshallingException` into :class:`~fields.MarshallingError`
- :class:`~fields.DateTime` field always output datetime