Fixed the URL for the node stats for version 1.x of ElasticSearch.

The monitor now first queries Elasticsearch to determine the version, and then based on this version it will choose the appropriate URL for the node stats. I also did some minor code cleanup along the way.

I tested this locally against Elasticsearch version 1.0.1 by running the controller and machineagent, associating the machineagent with an application and then verifying that I could see the metrics in the metric browser:

![screen shot 2014-04-22 at 3 40 59 pm](https://cloud.githubusercontent.com/assets/4431581/2772183/aaca506c-ca78-11e3-8b46-000f71fbd6ae.png)

David Winterbourne (principal engineer on the AppDynamics analytics team)