Spark Integration: Collect System Metrics from Spark Job

Build running here: https://builds.cask.co/browse/CDAP-DUT176-5

@anew : Please review. Thanks. 
Also, the API is a bit strange in a way that it passes in a `Location` and returns a `File`. If it has to be `File` all the time, why not just create a temp file and pass it in so that properties get written to it?