Add command: info

## What's up? 

This exposes the Heroku Plaform API command `app.info`, which returns a large object of information associated with the app. 

This is then sanitized to only include salient information. 

## Other stuff to note: 
- `helper.createRoom()` is now only called once because it caused memory leaks. We clear the messages in between tests instead. I'm sure this is a problematic approach because other state variables might not have been cleared when not recreating the room 
- Use `nock.cleanAll()` to clean up after each test. This ensures that one badly mocked test doesn't cause failures in tests after it 

Should probably set the buildpack_provided_description to a non null value for a better test.