Merge pull request #71 from dapper91/dev

- from_xml, from_xml_tree methods return type bound to cls type.
- wrapped sub-elements serialization bug fixed.

Merge pull request #62 from dapper91/dev

- forward refs support added. See #61

Merge pull request #59 from dapper91/dev

- piped union typehints support added. See #56

Merge pull request #53 from dapper91/dev

- model parameters inheritance bug fixed. See #51

Merge pull request #45 from dapper91/dev

- union types support added
- xml model encoding api unified with pydantic json encoding api
- root model validation raises exception instead of returning None
- xml model params inheritance implemented
- multiple element search strategies implemented
- serializers refactoring done, dead code removed

Merge pull request #35 from dapper91/dev

- ipaddress objects serialization support added
- py.typed file added
- distutils dependency removed
- default namespace redefinition during serialization fixed (for lxml only). See #27.

Merge pull request #22 from dapper91/dev

- field default parameter support added.
- field default_factory parameter support added.
- root model validation added.
- pydantic field alias support implemented.

Merge pull request #10 from dapper91/dev

- recursive (self-referencing) models support added.
- inherit_ns flag dropped due to recursive models implementation details.
- python 3.11 support added.

python 3.11 support added.

Merge pull request #7 from dapper91/dev

- attribute default namespace bug fixed.