def remove
      unless domain = shift_argument
        error("Usage: heroku domains:remove DOMAIN\nMust specify DOMAIN to remove.")
      end
      validate_arguments!
      action("Removing #{domain} from #{app}") do
        api.delete_domain(app, domain)
      end
    end
def remove
      unless domain = shift_argument
        error("Usage: heroku domains:remove DOMAIN\nMust specify DOMAIN to remove.")
      end
      validate_arguments!
      action("Removing #{domain} from #{app}") do
        api.delete_domain(app, domain)
      end
    end
domains:remove DOMAIN

 remove a custom domain from an app

Examples:

 $ heroku domains:remove example.com
 Removing example.com from example... done