monkey patch for a more light approach to rake paperclip:refresh

refresh_in_batches.rb

module Paperclip
  class << self
    def each_instance_with_attachment(klass, name)
      unscope_method = class_for(klass).respond_to?(:unscoped) ? :unscoped : :with_exclusive_scope
      class_for(klass).send(unscope_method) do
        class_for(klass).find_in_batches(:batch_size => 20) do |instance_batches|
          instance_batches.each do |instance|
            yield(instance) if instance.send(:"#{name}?")
          end
        end
      end
    end
  end
end