Include module in Cms::Acts::ContentPage needed for 'cms_site?' method

This fixes a bug found in CME project: Issues #1717 and #1843

Author: Steve Gray

lib/cms/acts/content_page.rb

@@ -11,7 +11,7 @@
 # Minor Issue:
 # Error handling for Page not found behaves slightly differently than ContentController currently. If the user is logged
 # in as an editor, they will get a 500 page rather than 404. This would require reworking how the error processing
-# works in Cms::ContentRenderingSupport. 
+# works in Cms::ContentRenderingSupport.
 module Cms
  module Acts
 
@@ -22,7 +22,7 @@ module PageHelper
  def cms_toolbar
  ""
  end
- 
+
  # If we are showing an error page, use that. Otherwise, just a blank page object that has a default title.
  def current_page
  super ? super : OpenStruct.new(page_title: controller.class.name.gsub("Controller", ""))
@@ -33,6 +33,7 @@ module ContentPage
  def self.included(base)
  base.send :include, Cms::ContentRenderingSupport
  base.send :include, Cms::Authentication::Controller
+ base.send :include, Cms::DomainSupport
  base.extend ClassMethods
 
  base.helper Cms::PageHelper