Now you can browse articles from a feed.

I'm sorting everything by reverse pubdate at the moment, but that
will be configurable later.

Also I avoid creating a new collection to store feed<->article
relationships, because I can easily query by "article.meta.xmlurl"
to find all articles for a feed. Maybe I can avoid storing feeds
themselves too, because I can also create a query to get all
distinct "article.meta.xmlurl" and just use that... may be too slow,
but I'll give it a try.
Switch from mongodb to mongoosejs
Remove debug output