Supervisor Resource capability configuration

Includes:
1. Ability to specify the supervisor resource (memory) through configuration, and finding the number of vcores based on the slots of the supervisor
2. Tracking the number of supervisors already running, so that only one supervisor can run per host.
3. Added a gitignore file to remove any files that should not be added to git

Notes:
1. I tried to set up the ApplicationMasterTrackingUrl to be the Storm UI page, but I guess the yarn proxy cannot handle the CSS correctly. It does not render the page correctly, so I kept that out of the pull request
2. I think that the best solution for the supervisor tracking would be to move to using the AMRMClientAsync. I had gone down this route but it required major modifications of code that probably wasn't necessary for what I wanted to do. 
3. I'm not sure how to write a test for this, any help would be appreciated.

Thanks