ui: load more entries when the bottom is reached
/subscriptions: added unread entry count
api.openid: added DEBUG_OVERRIDE_USER support
ui: show subscriptions' unread counts
ui: fixed click entry selection
api: added endpoint for adding subscriptions
ui: hide navbar for unauthorized people
feed.parse: change update_feed return value

update_feed now returns the feed object or None instead of True or False
respectively
ui: adding feeds