Website: Document dynamic code splitting with Webpack

[clebert]

• Will be closed by PR feat(all): add website package #208

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Dynamic Code Splitting With Webpack

Feature apps can use
webpack's dynamic code splitting feature
using the import() syntax.

To make this work for multiple feature apps living together on the Feature Hub
two configurations need to be made:

1. Set a unique value for
   output.jsonpFunction,
   e.g. "webpackJsonpMyFeatureApp".

2. Set
   output.publicPath
   to the public URL (relative or absolute) of the output directory, i.e. where
   all the feature app chunks are hosted.

   Since this is not always known at compile time, it can be left blank and set
   dynamically at runtime in the feature app's entry file using the global
   variable __webpack_public_path__. To help with that, createInstance is
   called with an env object that includes the publicPath of the feature
   app:

   export const featureApp = {
   	id,
   	dependencies,
   
   	createInstance(env) {
   		__webpack_public_path__ = env.publicPath;
   
   		return {
   			kind: 'react',
   			render: () => <div>Foo</div>,
   			isCompleted: () => true
   		};
   	}
   };