Minor cleanup

- Move 'temp file'
- Modify comments
- Run nginx on port 80
Added extra check on dns entry

Also moved role to gitstar_create_app in preparation for deletion task.
Adding handler for nginx restart

Handlers are only run in case of certain changes. In this case, we're
only running the nginx reload if the nginx config has changed.
Making app deploy a bit more robust

We now check to see if we have that version of the app image
created. If we do, then we just verify it's running, otherwise just run
it.