def admin_update_sort_order            
      params[:input_field_ids].each_with_index do |ip_id, i|
        ip = ModificationValueInputField.where(:id => ip_id).first
        ip.sort_order = i
        ip.save
      end      
      render :json => { :success => true }
    end
def admin_update_sort_order            
      params[:input_field_ids].each_with_index do |ip_id, i|
        ip = ModificationValueInputField.where(:id => ip_id).first
        ip.sort_order = i
        ip.save
      end      
      render :json => { :success => true }
    end
PUT /admin/products/:product_id/modifications/:mod_id/values/:mod_value_id/input-fields/sort-order