Add travis-ci

Author: developit

.travis.yml

@@ -0,0 +1,4 @@
+language: node_js
+node_js:
+  - "node"
+  - "iojs"

README.md

@@ -1,4 +1,7 @@
-# preact-render-to-string [![NPM](http://img.shields.io/npm/v/preact-render-to-string.svg)](https://www.npmjs.com/package/preact-render-to-string)
+# preact-render-to-string
+
+[![NPM](http://img.shields.io/npm/v/preact-render-to-string.svg)](https://www.npmjs.com/package/preact-render-to-string)
+[![travis-ci](https://travis-ci.org/developit/preact-render-to-string.svg)](https://travis-ci.org/developit/preact-render-to-string)
 
 Render JSX and [Preact] components to an HTML string.