including build status in readme

README.md

@@ -1,6 +1,7 @@
 #Gin Web Framework
 
 [![GoDoc](https://godoc.org/github.com/gin-gonic/gin?status.png)](https://godoc.org/github.com/gin-gonic/gin)
+[![Build Status](https://travis-ci.org/gin-gonic/gin.svg)](https://travis-ci.org/gin-gonic/gin)
 
 Gin is a web framework written in Golang. It features a martini-like API with much better performance, up to 40 times faster. If you need performance and good productivity, you will love Gin.  
 [Check out the official web site](http://gin-gonic.github.io/gin/)