Docs for react-router v4 basename feature

Fix facebook#2593

packages/react-scripts/template/README.md

@@ -1784,6 +1784,15 @@ To override this, specify the `homepage` in your `package.json`, for example:
 
 This will let Create React App correctly infer the root path to use in the generated HTML file.
 
+If you are using react-router v4 for your client side routing, it supports `basename` config in the `BrowserRouter`. For example:
+
+```js
+<BrowserRouter basename="/calendar"/>
+<Link to="/today"/> // renders <a href="/calendar/today">
+```
+
+So, all the `Link` component inside your app will navigate properly. Learn more [here](https://reacttraining.com/react-router/web/api/BrowserRouter/basename-string)
+
 #### Serving the Same Build from Different Paths
 
 >Note: this feature is available with `react-scripts@0.9.0` and higher.