docs(readme): add Greenkeeper badge

greenkeeper[bot] · greenkeeper[bot] · commit 15d7ed1c420e · 2017-05-09T01:20:28.000Z
diff --git a/README.md b/README.md
@@ -1,4 +1,6 @@
 # Javascript PHP Array
+
+[![Greenkeeper badge](https://badges.greenkeeper.io/rohmanhm/js-php-array.svg)](https://greenkeeper.io/)
 Use php array style in javascript
 
 ## How to use
