FIX: extract links in post processor

when oneboxes are not cached or are refreshed they can introduce new
links, these links must be extracted otherwise you can not follow them

lib/cooked_post_processor.rb

@@ -29,9 +29,16 @@ class CookedPostProcessor
       optimize_urls
       pull_hotlinked_images(bypass_bump)
       grant_badges
+      extract_links
     end
   end
 
+  # onebox may have added some links, so extract them now
+  def extract_links
+    TopicLink.extract_from(@post)
+    QuotedPost.extract_from(@post)
+  end
+
   def has_emoji?
     (@doc.css("img.emoji") - @doc.css(".quote img")).size > 0
   end