Register and process yaml tags when tags are set

[sirno]

Hi

I just went through the mildly painful process of trying to input data that includes local tags i.e. !TagName.

Anyway the way that dataclass_wizard handles the loading and dumping of such types is unfortunately not compatible with something like serde_yaml.

I adjusted __init_subclass__ to register custom loaders on yaml.SafeLoader and custom representers on yaml.SafeDumper to handle these cases. Obviously this is not quite clean, because these adjustments are now needed for the serialization and the encoder and decoder arguments should not be exposed in this case.

Also with this change attributes that are local class instances need these classes to be subclasses of YAMLWizard

It works for me. I will use it on my fork. If you want to adjust this to cleanly implement this into the meta class madness consider this a feature request.

Cheers

P.S. Thanks for maintaining this library! i use it a lot. and love it. <3