fix(package): update newrelic to version 6.4.0

Closes #48

Author: greenkeeper[bot]

package.json

@@ -18,7 +18,7 @@
     "commander": "^2.6.0",
     "debug": "^4.0.0",
     "fbp": "^1.1.2",
-    "newrelic": "^2.8.0",
+    "newrelic": "^6.4.0",
     "uuid": "^3.0.1"
   },
   "devDependencies": {