Even though I have `nginx_server_name` set in `production.rb` - I'm always prompted for "Nginx server name" on every deploy. Even for `bundle exec cap -T`!

I think the approach to setting the defaults should be different. For example, see how that's done in [capistrano/rbenv](https://github.com/capistrano/rbenv/blob/master/lib/capistrano/tasks/rbenv.rake#L33-49) project.