Merge pull request mozilla#30 from ajaxorg/master

UglifyJS moved to version 2, which is NOT backward compatible.

package.json

@@ -18,6 +18,6 @@
     { "type": "Apache-2.0", "url": "http://www.apache.org/licenses/LICENSE-2.0" }
   ],
   "dependencies": {
-    "uglify-js": ">=0.0.2"
+    "uglify-js": "~1.3.4"
   }
 }