chore(docs): Added commitizen badge

Author: joscha

README.md

@@ -4,6 +4,7 @@
 [![npm](https://img.shields.io/npm/l/crawlkit-runner-accessibility-developer-tools.svg)]()
 [![David](https://img.shields.io/david/crawlkit/runner-accessibility-developer-tools.svg)]()
 [![node](https://img.shields.io/node/v/crawlkit-runner-accessibility-developer-tools.svg)]()
+[![Commitizen friendly](https://img.shields.io/badge/commitizen-friendly-brightgreen.svg)](http://commitizen.github.io/cz-cli/)
 
 This runner can be used with [CrawlKit](https://github.com/crawlkit/crawlkit) in order to audit a website with the [Google Chrome Accessibility Developer Tools](https://github.com/GoogleChrome/accessibility-developer-tools).