fix: denodeify is needed in prod now too (#1879)

Author: hansl

package.json

@@ -52,6 +52,7 @@
     "copy-webpack-plugin": "^3.0.1",
     "core-js": "^2.4.0",
     "css-loader": "^0.23.1",
+    "denodeify": "^1.2.1",
     "ember-cli": "2.5.0",
     "ember-cli-string-utils": "^1.0.0",
     "enhanced-resolve": "^2.2.2",
@@ -126,7 +127,6 @@
     "@types/webpack": "^1.12.22-alpha",
     "chai": "^3.5.0",
     "conventional-changelog": "^1.1.0",
-    "denodeify": "^1.2.1",
     "dtsgenerator": "^0.7.1",
     "eslint": "^2.8.0",
     "exists-sync": "0.0.3",