Another huge commit.

Now uses OOP where it fits. Atom feeds are supported, but no real tests were made. Unix globbing is now possible for urls. Caching is done a cleaner way. Feedburner links are also replaced. HTML is cleaned a more efficient way. Code is now much cleaner, using lxml.objectify and a small wrapper to access Atom feeds as if they were RSS feeds (and much faster than feedparser). README has been updated.