Do not automatically include TheModerator::Model in ActiveRecord::Base

When automatically including the module in ActiveRecord::Base, it gives
a hierarchy error with Rails 4.
The module must be included in the required models.

lib/the_moderator.rb

@@ -2,5 +2,3 @@ require 'the_moderator/version'
 require 'the_moderator/exceptions'
 require 'the_moderator/model'
 require 'the_moderator/moderation_model'
-
-require 'the_moderator/railtie' if defined?(Rails)

lib/the_moderator/railtie.rb

@@ -1,9 +0,0 @@
-module TheModerator
-  class Railtie < Rails::Railtie
-    initializer "the_moderator.include_in_active_record" do
-      ActiveSupport.on_load :active_record do
-        include TheModerator::Model
-      end
-    end
-  end
-end