Better integration of articles in comments feed

We integrated articles into the comments feed so that it became much easier to discuss the articles and use articles in discussion. However, there was always the problem of going to the article itself to bid for the article, rather than the comment. Changing an article's summary didn't revise the article's summary in the comment feed.

All of this has been fixed. Now articles will show up in a shade of purple when they appear in the feed. Bidding on the article in the comments feed will bid on the article directly, and not a comment version of the article. Revisions to article summaries will be reflected in the discussion feeds.

Additionally, posts made by admins now appear in a shade of blue.