AC-8099: Upgrade underscore.js library to the latest version

Author: glo71317

lib/web/underscore.js

@@ -36,7 +36,7 @@
     "squirejs": "~0.2.1",
     "strip-json-comments": "~3.1.1",
     "time-grunt": "~2.0.0",
-    "underscore": "1.13.3"
+    "underscore": "1.13.6"
   },
  "overrides": {
    "styledocco": {