Change license to WTFPL and MIT.

Author: yonran

README.md

@@ -17,3 +17,7 @@ Usage:
 [Demo](http://yonran.github.com/detect-zoom/test-page.html)
 
 [Dimensions test](http://yonran.github.com/detect-zoom/tools/dimensions.html)
+
+License
+------
+Detect-zoom is dual-licensed under the WTFPL and MIT license, at the recipient's choice.

detect-zoom.js

@@ -1,6 +1,6 @@
-// BSD.
+// detect-zoom is dual-licensed under the WTFPL and MIT license,
+// at the recipient's choice.
 // https://github.com/yonran/detect-zoom/
-
 var DetectZoom = {
   mediaQueryBinarySearch: function(
       property, unit, a, b, maxIter, epsilon) {