should have a css line in a simple example (#271)

* should have a css line in a simple example

should have a css line in a simple example

* Add semicolon

Author: mikdatdogru

README.md

@@ -36,6 +36,7 @@ The development UMD build also needs the package `prop-types` being loaded besid
 
 ```js
 import { Tab, Tabs, TabList, TabPanel } from 'react-tabs';
+import "react-tabs/style/react-tabs.css";
 
 export default () => (
   <Tabs>