Fix rake bug.

lib/feeds/engine.rb

@@ -14,11 +14,13 @@ module Feeds
         base_url File.expand_path File.dirname(__FILE__)
         categorizable
         authorizable
+        if File.basename($0) != 'rake'
           begin
             avoid_page_cache SiteFeed
           rescue => e
             puts ["avoid_page_cache", e.to_s]
           end
+        end
         side_bar do
           head_label_i18n 'feed.feed', icon_class: "icons-rss"
           available_for "managers"