feat: add protractor config

mentioned in commit 464705e2

mentioned in merge request try-online!48 (merged)

mentioned in merge request stylish!8 (merged)

mentioned in merge request html-validate-vue-webpack-plugin!30 (merged)

mentioned in merge request cypress-html-validate!45 (merged)

mentioned in merge request dgeni-front-matter!31 (merged)

mentioned in merge request html-validate-jest-snapshot!41 (merged)

mentioned in merge request example-plugin!27 (merged)

mentioned in merge request html-validate-vue!78 (merged)

mentioned in merge request html-validate-angular!61 (merged)

mentioned in merge request html-validate!485 (merged)