# File lib/generators/paper_trail/install_generator.rb, line 30
    def add_paper_trail_migration(template)
      migration_dir = File.expand_path('db/migrate')

      unless self.class.migration_exists?(migration_dir, template)
        migration_template "#{template}.rb", "db/migrate/#{template}.rb"
      else
        warn("ALERT: Migration already exists named '#{template}'." +
               " Please check your migrations directory before re-running")
      end
    end