update README doc

Author: carloluis

README.md

@@ -1,10 +1,11 @@
-# webpack-demo
+# Webpack-Demo · [![GitHub license](https://img.shields.io/github/license/carloluis/webpack-demo.svg)](https://github.com/carloluis/webpack-demo/blob/master/LICENSE)
 
 This is a [webpack](https://webpack.js.org/) 4 demo project.
 
 ## Install webpack
 
 ```bash
+# add webpack 4 (currently on 4.0.0-beta.2)
 yarn add webpack@next webpack-cli --dev
 ```
 
@@ -22,9 +23,27 @@ On Webpack 4 they has defaults values:
 
 ### Mode
 
+Webpack mode reduce the required configuration for a useful build:
+
 * `production`: enables optimizations out of the box (scope hoisting, tree shaking, minification, etc.)
-* `development`: this mode is optimized for speed (un-minified bundle)
+* `development`: this mode provide useful error messages and is optimized for speed (un-minified bundle)
 
 ```bash
 webpack --mode production
 ```
+
+## Webpack Changes
+
+Full list of changes on [webpack changelog](https://github.com/webpack/webpack/releases).
+
+- Webpack dropped _Node.js 4_ support. Therefore, more benefits from ES6 features (optimizations from V8).
+- Sets of defaults with **production** and **development** modes.
+- General defaults (zero config file).
+
+More changes on [v4.0.0-beta.0](https://github.com/webpack/webpack/releases/tag/v4.0.0-beta.0)
+
+## Articles
+
+- [:rocket: webpack 4 beta — try it today! :rocket:](https://medium.com/webpack/webpack-4-beta-try-it-today-6b1d27d7d7e2)
+- [webpack 4: mode and optimization](https://medium.com/webpack/webpack-4-mode-and-optimization-5423a6bc597a)
+- [webpack 4: import() and CommonJs](https://medium.com/webpack/webpack-4-import-and-commonjs-d619d626b655)