Typical

pendulum` provides a factory function for converting an instance of `datetime.datetime` to `pendulum.DateTime`. We now us this factory if possible in the generated deserializer.

Improvements:
- Expanded benchmarks suite.
- Huge optimizations for functional/protocol API.
- Unify method for naming generated functions.
- Explicitly handle misconfigured serialization with clear error messages.

Bugfixes:
- Fixes conversion between path-types (resolves 88).
- Fixes validation of builtin types (resolves 89).
- Fixes validation of nested, constrained, optional types (These previously did not respect `optional/nullable` flags).

pathlib` makes use of meta-classes to determine the correct path-type on init. This caused validation to fail for Path sub-classes in Unions (85).

This fixes a regression in compiling mapping deserializers which was introduced when adding support for defaultdict, which caused optional mappings to fail to compile.

This resolves 83.

This adds a new lazy evaluation of field names during validation, saving any computational cost until error-reporting (resolves 81). Additionally, this is now appropriately type-safe for Mapping constraints (resolves 80).

This also iscreases the validation-strictness for high-level builtins (resolves 55).

This introduces the following changes:

- Improvement: Stricter validation of inputs for typed classes (78)
- Improvement: Cleaner reprs for Constraints more readable error reporting
- Bugfix: Always use the intersection of fields_in and value keys in des.