Bump lodash from 4.17.15 to 4.17.19

Bumps [lodash](https://github.com/lodash/lodash) from 4.17.15 to 4.17.19.
- [Release notes](https://github.com/lodash/lodash/releases)
- [Commits](lodash/lodash@4.17.15...4.17.19)

Signed-off-by: dependabot[bot] <support@github.com>

package.json

@@ -15,7 +15,7 @@
     "express": "~4.14.0",
     "formidable": "^1.1.1",
     "jade": "~1.11.0",
-    "lodash": "^4.17.4",
+    "lodash": "^4.17.19",
     "moment": "^2.18.1",
     "morgan": "~1.7.0",
     "node-schedule": "^1.2.1",