fix: server/package.json to reduce vulnerabilities (#33)

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/npm:base64url:20180511
- https://snyk.io/vuln/npm:cryptiles:20180710
- https://snyk.io/vuln/npm:extend:20180424
- https://snyk.io/vuln/npm:hoek:20180212
- https://snyk.io/vuln/npm:lodash:20180130
- https://snyk.io/vuln/npm:mime:20170907
- https://snyk.io/vuln/npm:node-forge:20180226
- https://snyk.io/vuln/npm:sshpk:20180409
- https://snyk.io/vuln/npm:stringstream:20180511
- https://snyk.io/vuln/npm:tough-cookie:20170905

Author: snyk-bot

server/package.json

@@ -5,7 +5,7 @@
     "async": "^2.5.0",
     "data-uri-to-buffer": "^2.0.0",
     "raven": "^2.1.0",
-    "request": "^2.81.0",
+    "request": "^2.84.0",
     "source-map": "^0.5.6",
     "url-join": "^2.0.2"
   },