Update README.md

Author: inhere

README.md

@@ -4,6 +4,7 @@
 [![Php Version](https://img.shields.io/badge/php-%3E=7.0-brightgreen.svg?maxAge=2592000)](https://packagist.org/packages/inhere/php-validate)
 [![Latest Stable Version](http://img.shields.io/packagist/v/inhere/php-validate.svg)](https://packagist.org/packages/inhere/php-validate)
 [![git branch](https://img.shields.io/badge/branch-master-yellow.svg)](https://github.com/inhere/php-validate)
+[![Build Status](https://travis-ci.org/inhere/php-validate.svg?branch=master)](https://travis-ci.org/inhere/php-validate)
 
 一个简洁小巧且功能完善的php验证、过滤库。仅有几个文件，无依赖。