Polyforce

Changed

- Rewriting of `polycheck`.

Added

- New [Polyfield](https://polyforce.tarsild.io/polyfield.md) for internal representation
- New [Field](https://polyforce.tarsild.io/polyfield#field) for generation of fields and defaults.

Fixed

- Fixed extraction of function information to generate the PolyFIeld.

Changed

* Refactor the whole core of decorator.
* Refactor the whole core of PolyModel.
* Refactor base metaclasse of PolyModel.
* Update tests.
* Add new `ValidationError` returning human readable messages.

Initial release of the **Polyforce**.