fix(package): update fastify to version 2.4.0

Closes #83

Author: greenkeeper[bot]

package.json

@@ -21,7 +21,7 @@
     "dotenv": "^6.0.0",
     "draconode": "^0.8.4",
     "dracotext": "^1.3.2",
-    "fastify": "^1.12.0",
+    "fastify": "^2.4.0",
     "geolib": "^2.0.24",
     "googlemaps": "^1.12.0",
     "lodash": "^4.17.11",