Code refactor on the way to adding special feeds
Normalize config keys and add show_special_folders option
Rename markRead to markArticleRead
Remove redundant call to update view-home
Refactor markArticleRead to make use of markFeedRead
Show feed icons for articles when reading a special feed

When reading an article update special feed and parent feed
Add support for special feeds

Add icons to feed and articles when viewed from special feed
Add settings view to disable showing special feeds
Verified that CORs works