feat: add travis badge

Author: juristr

README.md

@@ -1,6 +1,7 @@
 ## Angular Tabs - Demo Library
 
 [![semantic-release](https://img.shields.io/badge/%20%20%F0%9F%93%A6%F0%9F%9A%80-semantic--release-e10079.svg)](https://github.com/semantic-release/semantic-release)
+[![Build Status](https://travis-ci.org/juristr/ngx-tabs-libdemo.svg?branch=v0.0.0-development)](https://travis-ci.org/juristr/ngx-tabs-libdemo)
 
 **WARNING**: This is not a production ready library, but rather just an example
 to showcase how to release custom Angular libraries.