docs(README): conventional commits badge

Signed-off-by: Vojtech Masek <[email protected]>

Author: vmasek

README.md

@@ -3,6 +3,7 @@
 [![npm](https://img.shields.io/npm/dm/%40flowup/api-client-generator.svg)](https://www.npmjs.com/package/api-client-generator)
 
 [![Caretaker](https://img.shields.io/badge/caretaker-vmasek-blue.svg)](https://github.com/vmasek)
+[![Conventional Commits](https://img.shields.io/badge/Conventional%20Commits-1.0.0-yellow.svg)](https://conventionalcommits.org)
 
 [![GitHub stars](https://img.shields.io/github/stars/flowup/api-client-generator.svg?style=social&label=Star)](https://github.com/flowup/api-client-generator)
 [![Twitter URL](https://img.shields.io/twitter/url/http/flowup.cz.svg?style=social)](https://twitter.com/intent/tweet?text=Tool%20that%20lets%20you%20generate%20API%20client%20from%20a%20swagger%20file&hashtags=angular,swagger,api,angular5&url=https://github.com/flowup/api-client-generator)