Demonstrate @babel/preset-env with ESModules targetting

With the release of Babel 7 one can now specifically target devices supporting ESModules.

This can greatly reduce the amount of JavaScript sent to modern devices with minimal effort.

This example shows how one can apply the technique.

Installation

1. Clone this repo.
2. yarn to install dependencies.
3. yarn start to startup a localhost:3000 server with a sample page.

Good luck, and let's send users less JavaScript!