Configure a working development environment for testing in the broswer

[jgaehring]

I'm optimistic this can be achieved just by modifying the Webpack dev config, specifically settings on the devServer. The proxy, headers and https properties seem most relevant.

If using the farmOS Docker image as a development backend, it will probably also require some configuration with the Drupal CORS module.

[jgaehring]

Just dumping some links here for reference... two different approaches for configuring Webpack for issues like ours:

webpack/webpack-dev-server#533 (comment)
https://stackoverflow.com/questions/31602697/webpack-dev-server-cors-issue

[jgaehring]

Finally resolved with 562d55d, just updating the documentation page now.