Added missing dependency to gulp

package.json

@@ -9,7 +9,8 @@
     "gulp-less": "^3.0.3",
     "gulp-minify-css": "^1.2.0",
     "gulp-rename": "^1.2.2",
-    "gulp-watch": "^4.3.1"
+    "gulp-watch": "^4.3.1",
+    "gulp": "^3.9.0"
   },
   "devDependencies": {},
   "scripts": {