Update README.md

Author: Igor Chepurnoy

README.md

@@ -4,6 +4,7 @@ Schedule extension for Yii2
 This extension is the port of Laravel's Schedule component (http://laravel.com/docs/master/artisan#scheduling-artisan-commands)
 
 [![Latest Stable Version](https://poser.pugx.org/yii2mod/yii2-scheduling/v/stable)](https://packagist.org/packages/yii2mod/yii2-scheduling)  [![Total Downloads](https://poser.pugx.org/yii2mod/yii2-scheduling/downloads)](https://packagist.org/packages/yii2mod/yii2-scheduling)
+[![Build Status](https://travis-ci.org/yii2mod/yii2-scheduling.svg?branch=master)](https://travis-ci.org/yii2mod/yii2-scheduling)
 
 Installation
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