fix: package.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-JSONPOINTER-598804
- https://snyk.io/vuln/SNYK-JS-HAWK-6969142
- https://snyk.io/vuln/SNYK-JS-IP-6240864
- https://snyk.io/vuln/npm:base64url:20180511
- https://snyk.io/vuln/SNYK-JS-LODASH-567746
- https://snyk.io/vuln/SNYK-JS-PACRESOLVER-1564857
- https://snyk.io/vuln/SNYK-JS-NETMASK-1089716
- https://snyk.io/vuln/SNYK-JS-NETMASK-6056519
- https://snyk.io/vuln/SNYK-JS-ISMYJSONVALID-597165
- https://snyk.io/vuln/SNYK-JS-LODASH-6139239
- https://snyk.io/vuln/SNYK-JS-QS-3153490
- https://snyk.io/vuln/SNYK-JS-SEMVER-3247795
- https://snyk.io/vuln/npm:sshpk:20180409
- https://snyk.io/vuln/SNYK-JS-ISMYJSONVALID-597167
- https://snyk.io/vuln/SNYK-JS-LODASH-608086
- https://snyk.io/vuln/SNYK-JS-Y18N-1021887
- https://snyk.io/vuln/SNYK-JS-LODASH-1040724
- https://snyk.io/vuln/SNYK-JS-IP-7148531
- https://snyk.io/vuln/SNYK-JS-REQUEST-3361831
- https://snyk.io/vuln/SNYK-JS-TOUGHCOOKIE-5672873
- https://snyk.io/vuln/npm:stringstream:20180511
- https://snyk.io/vuln/SNYK-JS-JSONSCHEMA-1920922
- https://snyk.io/vuln/npm:hoek:20180212
- https://snyk.io/vuln/SNYK-JS-AJV-584908
- https://snyk.io/vuln/SNYK-JS-JSONPOINTER-1577288
- https://snyk.io/vuln/npm:forwarded:20170908
- https://snyk.io/vuln/npm:fresh:20170908
- https://snyk.io/vuln/npm:qs:20170213
- https://snyk.io/vuln/SNYK-JS-LODASH-1018905
- https://snyk.io/vuln/SNYK-JS-HAWK-2808852
- https://snyk.io/vuln/npm:extend:20180424
- https://snyk.io/vuln/npm:tunnel-agent:20170305
- https://snyk.io/vuln/npm:is-my-json-valid:20180214
- https://snyk.io/vuln/npm:tough-cookie:20170905
- https://snyk.io/vuln/SNYK-JS-WORDWRAP-3149973
- https://snyk.io/vuln/npm:debug:20170905
- https://snyk.io/vuln/npm:mime:20170907
- https://snyk.io/vuln/npm:ms:20170412

package.json

@@ -35,19 +35,19 @@
     ]
   },
   "dependencies": {
-    "auth0": "2.17.0",
-    "auth0-extension-express-tools": "^1.1.9",
+    "auth0": "4.0.0",
+    "auth0-extension-express-tools": "^2.0.1",
     "auth0-extension-tools": "^1.3.3",
     "auth0-oauth2-express": "1.2.0",
     "body-parser": "^1.15.2",
     "cors": "2.8.1",
     "crypto": "^0.0.3",
-    "express": "4.14.0",
-    "express-jwt": "^5.1.0",
+    "express": "4.16.0",
+    "express-jwt": "^7.2.0",
     "handlebars": "^4.0.5",
-    "jsonwebtoken": "^7.1.9",
+    "jsonwebtoken": "^8.5.0",
     "lodash": "^4.16.4",
-    "nconf": "^0.8.4",
+    "nconf": "^0.11.0",
     "webtask-tools": "^3.1.0",
     "winston": "^2.2.0"
   },