Improve rails integration

lib/datagrid.rb

@@ -1,5 +1,6 @@
 require "action_view"
 require "datagrid/configuration"
+require "datagrid/engine"
 
 module Datagrid
 
@@ -14,14 +15,7 @@ module Datagrid
   autoload :Configuration
 
   autoload :Helper
-  ::ActiveSupport.on_load(:action_view) do
-    ActionView::Base.send(:include, Datagrid::Helper)
-  end
-
   autoload :FormBuilder
-  ::ActiveSupport.on_load(:action_view) do
-    ActionView::Helpers::FormBuilder.send(:include, Datagrid::FormBuilder)
-  end
 
   autoload :Renderer
 

lib/datagrid/engine.rb

@@ -1,12 +1,14 @@
 require "rails/engine"
+require 'datagrid/helper'
+require 'datagrid/form_builder'
 
 module Datagrid
   # @!private
   class Engine < ::Rails::Engine
     initializer "datagrid.helpers" do
-      #TODO: check why it doesn't work
       ActiveSupport.on_load :action_view do
-        include Datagrid::Helper
+        ActionView::Base.send(:include, Datagrid::Helper)
+        ActionView::Helpers::FormBuilder.send(:include, Datagrid::FormBuilder)
       end
     end
   end

lib/datagrid/helper.rb

@@ -1,4 +1,3 @@
-require "datagrid/engine"
 require "action_view"
 
 module Datagrid