Fix npm version badge

README.md

@@ -5,7 +5,7 @@
 [![Maintenance](https://img.shields.io/badge/Maintained%3F-yes-green.svg)](https://github.com/naptha/tesseract.js/graphs/commit-activity)
 
 [![Build Status](https://travis-ci.org/naptha/tesseract.js.svg?branch=develop)](https://travis-ci.org/naptha/tesseract.js)
-[![NPM version][tesseractjs-npm-image]][tesseractjs-npm-url]
+[![npm version](https://badge.fury.io/js/tesseract.js.svg)](https://badge.fury.io/js/tesseract.js)
 [![Downloads Total](https://img.shields.io/npm/dt/tesseract.js.svg)](https://www.npmjs.com/package/tesseract.js)
 [![Downloads Month](https://img.shields.io/npm/dm/tesseract.js.svg)](https://www.npmjs.com/package/tesseract.js)