[CI] Remove badge for Travis (#233)

Author: Nyholm

README.md

@@ -1,7 +1,6 @@
 # PSR-7 implementation
 
 [![Latest Version](https://img.shields.io/github/release/Nyholm/psr7.svg?style=flat-square)](https://github.com/Nyholm/psr7/releases)
-[![Build Status](https://img.shields.io/travis/Nyholm/psr7/master.svg?style=flat-square)](https://travis-ci.org/Nyholm/psr7)
 [![Total Downloads](https://poser.pugx.org/nyholm/psr7/downloads)](https://packagist.org/packages/nyholm/psr7)
 [![Monthly Downloads](https://poser.pugx.org/nyholm/psr7/d/monthly.png)](https://packagist.org/packages/nyholm/psr7)
 [![Software License](https://img.shields.io/badge/license-MIT-brightgreen.svg?style=flat-square)](LICENSE)