fix: package.json & .snyk to reduce vulnerabilities

The following vulnerabilities are fixed with a Snyk patch:
- https://snyk.io/vuln/SNYK-JS-LODASH-567746

package.json

@@ -4,7 +4,9 @@
   "description": "Ofertas de empleo de calidad para desarrolladores de calidad",
   "main": "server.js",
   "scripts": {
-    "start": "node server.js"
+    "start": "node server.js",
+    "snyk-protect": "snyk protect",
+    "prepublish": "npm run snyk-protect"
   },
   "author": "Ulises Gascón",
   "contributors": [
@@ -27,6 +29,8 @@
     "slack-node": "0.2.0",
     "socket.io": "1.4.8",
     "twitter": "1.3.0",
-    "x-ray": "2.3.0"
-  }
+    "x-ray": "2.3.0",
+    "snyk": "^1.316.1"
+  },
+  "snyk": true
 }