add enzyme api documents

Author: hustcc

README.md

@@ -37,4 +37,5 @@ npm test
 2. [从工程化角度讨论如何快速构建可靠 React 组件](https://github.com/lcxfs1991/blog/issues/18?hmsr=toutiao.io&utm_medium=toutiao.io&utm_source=toutiao.io)
 3. [How React Components Make UI Testing Easy](https://www.toptal.com/react/how-react-components-make-ui-testing-easy)
 4. [jest API documents](http://facebook.github.io/jest/docs/api.html)
-5. [使用 Jest + Enzyme 测试 React 应用](https://www.atatech.org/articles/74344)
+5. [enzyme API documents](https://github.com/airbnb/enzyme/blob/master/docs/api)
+6. [使用 Jest + Enzyme 测试 React 应用](https://www.atatech.org/articles/74344)