fix(package): update commander to version 4.0.0

Closes #232

Author: greenkeeper[bot]

package.json

@@ -21,7 +21,7 @@
     "amqplib": "^0.5.1",
     "async": "^2.5.0",
     "coffeescript": "^2.0.2",
-    "commander": "^2.10.0",
+    "commander": "^4.0.0",
     "debug": "^4.0.0",
     "fbp": "^1.6.0",
     "mqtt": "^2.7.1",