add node image

Author: fengmk2

README.md

@@ -2,12 +2,15 @@ jsonp-body
 =======
 
 [![NPM version][npm-image]][npm-url]
+[![node version][node-image]][node-url]
 [![build status][travis-image]][travis-url]
 [![Test coverage][coveralls-image]][coveralls-url]
 [![Gittip][gittip-image]][gittip-url]
 
 [npm-image]: https://img.shields.io/npm/v/jsonp-body.svg?style=flat-square
 [npm-url]: https://npmjs.org/package/jsonp-body
+[node-image]: https://img.shields.io/badge/node.js-%3E=_0.10-green.svg?style=flat-square
+[node-url]: http://nodejs.org/download/
 [travis-image]: https://img.shields.io/travis/node-modules/jsonp-body.svg?style=flat-square
 [travis-url]: https://travis-ci.org/node-modules/jsonp-body
 [coveralls-image]: https://img.shields.io/coveralls/node-modules/jsonp-body.svg?style=flat-square