docs(readme): update README.md

Author: lzhfe

README.md

@@ -1,11 +1,10 @@
-# hello-world
-Hello-world project for Angular 2 with webpack
+# Hello-World
+Hello-world project for Angular 2 with webpack, example in this book “揭秘Angular 2”.
 
 ## Usage
 
 - Clone or fork this repository
-- Make sure you have node.js(>V4.0.0) installed
-- run npm install -g webpack webpack-dev-server typescript to install global dependencies
-- run npm install to install dependencies
-- run npm start to fire up dev server
+- Make sure you have node.js(> 4.0) installed
+- run `npm install` to install dependencies
+- run `npm start` to fire up dev server
 - open browser to http://localhost:3000