fix: package.json to reduce vulnerabilities

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

Latest report for fiddur/some-comments:
https://snyk.io/test/github/fiddur/some-comments

package.json

@@ -21,7 +21,7 @@
     "cors": "^2.5.3",
     "express": "^4.12.3",
     "express-handlebars": "^2.0.1",
-    "grunt": "^0.4.5",
+    "grunt": "^1.0.3",
     "handlebars": "^3.0.3",
     "jade": "^1.9.2",
     "jsonwebtoken": "^5.0.1",