Update grunt-contrib-uglify dependency.

package.json

@@ -39,7 +39,7 @@
     "grunt-contrib-jshint": "~0.8.0",
     "grunt-contrib-less": "~0.9.0",
     "grunt-contrib-qunit": "~0.4.0",
-    "grunt-contrib-uglify": "~0.2.7",
+    "grunt-contrib-uglify": "~0.3.0",
     "grunt-contrib-watch": "~0.5.3",
     "grunt-csscomb": "~2.0.1",
     "grunt-html-validation": "~0.1.13",