Add instruction to add module

Author: PowerKiKi

README.md

@@ -1,3 +1,5 @@
 ## Angular UI homepage
 
-To modify Angular UI homepage, edit index.html and push to GitHub. See the result at: http://angular-ui.github.io/
+To modify Angular UI homepage, edit index.html and push to GitHub. See the result at: http://angular-ui.github.io/
+
+To add a new module, insert it at the end of the ``modules`` array in ``js/app.js``.