docs: add details to readme

README.md

@@ -1,3 +1,28 @@
 # Hong Kong Identity Card Number Generator and Validator #
 
-Progressive Web Application for generates or validates Hong Kong Identity Card number.
+Progressive Web Application for generates or validates Hong Kong Identity Card number.
+
+## Preview Screens ##
+![Generator](./docs/hkid-generator-home.png)
+![Validator](./docs/hkid-generator-validator.png)
+
+## Setup ##
+Below shows some basic setup steps.
+
+### Node version ###
+This project is developed using Node.js 10. The version is already specified in the `.nvmrc` file. Suggest to run `nvm use` when you enter the project folder.
+
+### Install packages need for the project ###
+Install npm packages in project root folder first using `npm install`.
+
+### To start the project ##
+Run `npm dev` in project root folder.
+
+### To build production ###
+Run `npm build` in project root folder.
+
+## Configurations ##
+Below shows some available configuration options.
+
+### To add / edit Webpack alias ###
+To add or edit Webpack alias, modify `resolve.alias` in `webpack/webpack.base.conf.js`.