Add a CONTRIBUTING.md explaining how to run the tests
Add a CONTRIBUTING.md explaining how to run the tests

domenic/html-as-custom-elements,domenic/html-as-custom-elements,valmzetvn/html-as-custom-elements,valmzetvn/html-as-custom-elements,zenorocha/html-as-custom-elements,zenorocha/html-as-custom-elements,valmzetvn/html-as-custom-elements,domenic/html-as-custom-elements