add Travis badges

README.md

@@ -45,7 +45,7 @@ See also http://arewewebyet.com/
     * [carllerche/curl-rust](https://github.com/carllerche/curl-rust) — [libcurl](http://curl.haxx.se/libcurl/) bindings
   * server
     * [erickt/rust-mongrel2](https://github.com/erickt/rust-mongrel2) — [Mongrel2](http://mongrel2.org) bindings
-    * [Iron](http://ironframework.io/) — inspired by [Express](http://expressjs.com/).
+    * [Iron](http://ironframework.io/) — inspired by [Express](http://expressjs.com/). [<img src="https://travis-ci.org/iron/iron.png?branch=master">](https://travis-ci.org/iron/iron)
     * [Nickel](http://nickel.rs/) — inspired by [Express](http://expressjs.com/).
 
 ## Resources