Merge pull request #1 from dkhamsing/patch-1

Add link to Threes

README.md

@@ -32,4 +32,4 @@ License
 -------
 (c) 2014 Austin Zheng. Released under the terms of the MIT license.
 
-2048 by Gabriele Cirulli (http://gabrielecirulli.com/). The original game can be found at http://gabrielecirulli.github.io/2048/, as can all relevant attributions. 2048 is inspired by an iOS game called "Threes", by Asher Vollmer.
+2048 by Gabriele Cirulli (http://gabrielecirulli.com/). The original game can be found at http://gabrielecirulli.github.io/2048/, as can all relevant attributions. 2048 is inspired by an iOS game called [Threes](http://asherv.com/threes/), by Asher Vollmer.