fix: package.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/npm:diff:20180305
- https://snyk.io/vuln/npm:lodash:20180130

package.json

@@ -47,9 +47,9 @@
     "bluebird": "^3.5.0",
     "chalk": "^1.1.3",
     "commander": "^2.9.0",
-    "diff": "^3.2.0",
+    "diff": "^3.5.0",
     "handlebars": "^4.0.6",
-    "lodash": "^4.17.4"
+    "lodash": "^4.17.5"
   },
   "devDependencies": {
     "app-root-path": "^2.0.1",