- added react

  - added react files from CRA
  - added hot reloading

- migrated typescript

  - fixed @types/node version to ^12 to fix type warnings Ref. [issue](https://github.com/electron/electron/issues/21612)
  - skip type checking in renderer index.ts as a demo page with vue is added without types.

- cloned from [electron-webpack-quick-start](https://github.com/electron-userland/electron-webpack-quick-start)