doc: add shield icons

Author: Tidyzq

README.md

@@ -1,4 +1,11 @@
 ## WeUI组件库简介
+
+[![](https://img.shields.io/npm/v/weui-miniprogram.svg?style=flat-square)](https://www.npmjs.com/package/weui-miniprogram)
+[![](https://img.shields.io/npm/dw/weui-miniprogram?style=flat-square)](https://www.npmjs.com/package/weui-miniprogram)
+[![](https://img.shields.io/travis/wechat-miniprogram/weui-miniprogram.svg?style=flat-square)](https://github.com/wechat-miniprogram/weui-miniprogram)
+[![](https://img.shields.io/github/license/wechat-miniprogram/weui-miniprogram.svg?style=flat-square)](https://github.com/wechat-miniprogram/weui-miniprogram)
+[![](https://img.shields.io/codecov/c/github/wechat-miniprogram/weui-miniprogram.svg?style=flat-square)](https://github.com/wechat-miniprogram/weui-miniprogram)
+
 这是一套基于样式库[weui-wxss](https://github.com/Tencent/weui-wxss/)开发的小程序扩展组件库，同微信原生视觉体验一致的扩展组件库，由微信官方设计团队和小程序团队为微信小程序量身设计，令用户的使用感知更加统一。
 
 ## 如何使用