chore: update devDependencies

Author: wesleycho

Diff for: package.json

@@ -19,9 +19,9 @@
     "grunt-contrib-concat": "^0.5.1",
     "grunt-contrib-copy": "^0.8.0",
     "grunt-contrib-jshint": "^0.11.1",
-    "grunt-contrib-uglify": "^0.9.1",
+    "grunt-contrib-uglify": "^0.10.0",
     "grunt-contrib-watch": "^0.6.1",
-    "grunt-conventional-changelog": "^4.0.0",
+    "grunt-conventional-changelog": "^5.0.0",
     "grunt-ddescribe-iit": "0.0.6",
     "grunt-html2js": "^0.3.0",
     "grunt-karma": "^0.12.0",