Update dependencies to enable Greenkeeper 🌴 (#3940)

* chore(package): update dependencies

* docs(readme): add Greenkeeper badge

* Fix indent issues with eslint 4.0

see http://eslint.org/docs/user-guide/migrating-to-4.0.0\#-the-indent-rule-is-more-strict

src/StatusHandler.js

@@ -159,7 +159,7 @@ export function pushStatusHandler(config, objectId = newObjectId()) {
   const setRunning = function(count) {
     logger.verbose(`_PushStatus ${objectId}: sending push to %d installations`, count);
     return handler.update({status:"pending", objectId: objectId},
-        {status: "running", updatedAt: new Date(), count });
+      {status: "running", updatedAt: new Date(), count });
   }
 
   const trackSent = function(results) {