Xsdata

- Added field metadata key `tokens` for xs:list or xs:NMTOKENS derived elements.
- Added datatype factory to register custom converters.
- Added XmlHandler interface to decouple parsing from lxml.
- Added lxml based content handlers: LxmlEventHandler, LxmlSaxHandler
- Added native python xml content handlers: XmlEventHandler, XmlSaxHandler
- Added support for python >= 3.6 [241](https://github.com/tefra/xsdata/issues/241)
- Added codegen for soap 1.1 fault messages.
- Fixed converting to enum members derived from xs:NMTOKENS.
- Fixed package level import naming conflicts.
[228](https://github.com/tefra/xsdata/issues/206)
- Fixed xml serializing to allow empty strings in attribute values.
[230](https://github.com/tefra/xsdata/issues/230)
- Fixed xml serializing for mixed content with non generics.
[238](https://github.com/tefra/xsdata/issues/238)

- Added codegen support for **WSDL 1.1 and SOAP 1.1** bindings.
- Added experimental web services client.
- Added cli flag `--ns-struct` to group classes by target namespaces.
[206](https://github.com/tefra/xsdata/issues/206)
- Added parser config to support xinclude statements.
[207](https://github.com/tefra/xsdata/issues/207)
- Added new xml union node to improve bindings for fields with union type.
[207](https://github.com/tefra/xsdata/issues/207)
- Fixed class resolve issue with mixed namespaces.
[204](https://github.com/tefra/xsdata/issues/204)
- Fixed attribute comparison issue. [209](https://github.com/tefra/xsdata/issues/209)
- Fixed data type mapping for various schema elements.
[221](https://github.com/tefra/xsdata/issues/221)
- Fixed mixed content handling. [213](https://github.com/tefra/xsdata/issues/213)
- Code cleanup & 100% coverage.

- Updated analyzer to allow abstract types to be generated.
[199](https://github.com/tefra/xsdata/issues/199)
- Removed support to generate code from multiple sources.
[172](https://github.com/tefra/xsdata/issues/172)
- Fixed naming conflict with AttributeGroup analyzer handler.
[194](https://github.com/tefra/xsdata/issues/194)
- Fixed analyzer to merge redefined attribute groups.
[196](https://github.com/tefra/xsdata/issues/196)
- Fixed analyzer to block inheritance on xs:override derived types.
[198](https://github.com/tefra/xsdata/issues/198)
- Refactored code to prepare for wsdl support.

- Updated XmlSerializer to render default namespace whenever possible.
- Fixed issue generating modules outside the target package.
- Fixed issue not creating nested package **init** files.
- Code cleanup & docstrings

- Added version option in the xsdata cli.
- Added generation of missing python **init** files.
- Added support for default values to inner enum classes.
- Fixed multiple issues with abstract classes and attributes/extension flattening.
- Fixed instance cross references causing codegen unpredictable results.
- Fixed xml serialization of wildcard attributes with user defined model values.
- Fixed issue with redefined/override elements with annotations.
- Fixed expand attribute groups recursively.
- Fixed false positive circular references.
- Fixed enumeration unions detection.
- Refactored ClassAnalyzer to smaller components.

- Fix flattening enumeration unions.
- Fix generation for enum fields with default/fixed value.
- Fix duplicate attribute names handler to be case-insensitive.