update LICENSE.txt

LICENSE.txt

 ==============================================
 This is a copy of the MIT license.
 ==============================================
-Copyright (C) 2012, 2013 Mort Yao <mort.yao@gmail.com>
+Copyright (C) 2012, 2013, 2014 Mort Yao <mort.yao@gmail.com>
 Copyright (C) 2012 Boyu Guo <iambus@gmail.com>
 
 Permission is hereby granted, free of charge, to any person obtaining a copy of