0.6.4: Support dataframe-level checks in SchemaModel Config, Bugfixes

New Features

• Allow attaching registered dataframe checks by using Config field names (#478)

Bugfixes

• alias propagation works correctly on empty subclass (#446)
• Add missing inplace arg to SchemaModel's validate (#450)
• fix check_types decorator should return results from validate (#458)
• Dataframe schemas in yaml do not require any field (#479)
• coerce=True and pandas_dtype=None should be a noop (#476)

Doc Improvement

• update documentation css to fit mobile (#447)
• add copy button to docs (#448)
• link documentation to github (#449)

Infrastructure Changes

• add bugfixes and release branches to github actions eb38173
• fix github action triggers 3191be9
• update bug report template b0db5b0
• bump cache 0ee703f
• noxfile fixes 489695d
• update pylint (#477)