* starting validation_decorator
* correct skip_pre_38
* fix coverage and type hints
* mypy tests and move to class based decorator
* 3.6 fix, prevent duplicate github actions
* correct py 3.6 check
* better errors
* cleaner field names for args and kwargs
* add change and comments
* starting docs
* back to 3.7 for docs
* docs
* bump
* add async example and fix print indents
* allow type annotations as strings
* python 3.8 in docs
Samuel Colvin