* config(dev): remove unused polyfills in webpack-dev

Co-authored-by: Pontus Wallberg <pontus.wallberg@configura.com>

* es2015 bundle with dependencies via npm script build🇪🇸bundle
* es2015 bundle without dependencies via npm script build🇪🇸bundle
* jest dependency for test:artifact
* migrate babel.config.json to babel.config.js and maintain env support for commonjs and es2015
* remove polyfill
* fix es syntax: replace module.exports with export
* fix es syntax: remove .jsx extension inside import

* build new core webpack config

* fix exports in Webpack; use ESM syntax throughout

* add bundle config

* add standalone config

* add style config

* prettier...

* add dev config

* delete legacy webpack scripts

* rewire npm scripts to use new webpack configs

* cache babel-loader results

* fix e2e dev servers

* update core Webpack modules

* update loaders to latest

* remove unused loaders

* update Webpack plugins

* add mode flags to Webpack configs

* remove plugin invocations that are now production-standard in v4

* update webpack-cli

* add webpack perf size limit flags

* replace ExtractText with MiniCssExtract + IgnoreAssets

* UglifyJsPlugin -> TerserPlugin

* fix PostCSS processing

* enable Terser sourcemaps

* webpack/style -> webpack/stylesheets