Add @license directive for preserving comments w/uglify

src/color-thief.js

@@ -1,4 +1,4 @@
-/*!
+/*
  * Color Thief v2.0
  * by Lokesh Dhakar - http://www.lokeshdhakar.com
  *
@@ -14,6 +14,7 @@
  * Released under the MIT license
  * https://raw.githubusercontent.com/lokesh/color-thief/master/LICENSE
  *
+ * @license
  */
 
 
@@ -143,6 +144,7 @@ ColorThief.prototype.getPalette = function(sourceImage, colorCount, quality) {
 /*!
  * quantize.js Copyright 2008 Nick Rabinowitz.
  * Licensed under the MIT license: http://www.opensource.org/licenses/mit-license.php
+ * @license
  */
 
 // fill out a couple protovis dependencies
@@ -150,6 +152,7 @@ ColorThief.prototype.getPalette = function(sourceImage, colorCount, quality) {
  * Block below copied from Protovis: http://mbostock.github.com/protovis/
  * Copyright 2010 Stanford Visualization Group
  * Licensed under the BSD License: http://www.opensource.org/licenses/bsd-license.php
+ * @license
  */
 if (!pv) {
     var pv = {