Closed requested to merge upgrade_deps into react
…to work with newer versions of node and because it is the future™.
- replacing eslint-loader with eslint-webpack-plugin
- using a fork of offline-plugin working with v5
- using webpack serve instead of webpack-dev-server command, adjust to renamed configuration options
- use new built-in Web Workers support see (https://webpack.js.org/guides/web-workers/)
- downgrade used version of d3 types to match used library version
- fixed import issue