remove advertisement code

lib/tasks/images.rake

@@ -104,16 +104,7 @@ namespace :images do
     upload.generate_resizes(post.file_path)
     post.distribute_files
   end
-  
-  desc "Finds advertisement images that don't exist"
-  task :find_missing_ads => :environment do
-    Advertisement.where("status = 'active'").each do |ad|
-      if !File.exists?(ad.image_path)
-        puts ad.image_path
-      end
-    end
-  end
-  
+    
   desc "Generate thumbnail-sized images of posts"
   task :generate_preview => :environment do
     Post.where("image_width > ?", Danbooru.config.small_image_width).find_each do |post|