fix(package): update commander to version 4.1.1

Closes #62

Author: greenkeeper[bot]

package.json

@@ -15,7 +15,7 @@
     "async": "^2.1.4",
     "chance": "^1.0.4",
     "coffeescript": "^2.0.2",
-    "commander": "^2.6.0",
+    "commander": "^4.1.1",
     "debug": "^4.0.0",
     "fbp": "^1.1.2",
     "newrelic": "^2.8.0",