Update Readme.markdown to point at the updated mustache.github.com url.

Conflicts:
	vendor/spec

README.markdown

@@ -1,7 +1,7 @@
 Mustache.php
 ============
 
-A [Mustache](http://defunkt.github.com/mustache/) implementation in PHP.
+A [Mustache](http://mustache.github.com/) implementation in PHP.
 
 [![Build Status](https://secure.travis-ci.org/bobthecow/mustache.php.png?branch=dev)](http://travis-ci.org/bobthecow/mustache.php)