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- Refactor Swagger UI handling:
- allow to register a custom view with ``api.documentation``
- allow to register a custom URL with the ``doc`` parameter
- allow to disable documentation with ``doc=False``
- Added fields mask support through header (see: :doc:`Fields Masks Documentation </mask>`)
- Expose ``flask_restful.inputs`` module on ``flask_restplus.inputs``
- Added support for some missing fields and attributes:
- ``host`` root field (filed only if ``SERVER_NAME`` config is set)
- custom ``tags`` root field
- ``exclusiveMinimum`` and ``exclusiveMaximum`` number field attributes
- ``multipleOf`` number field attribute
- ``minLength`` and ``maxLength`` string field attributes
- ``pattern`` string field attribute
- ``minItems`` and ``maxItems`` list field attributes
- ``uniqueItems`` list field attribute
- Allow to override the default error handler
- Fixes