Sort chats and roster by unreadMsg

Contacts with unread messages are now on top of the list. I need to
change the way presence is stored in the db, so I could add sorting this
way too. So first unread messages, then presence, then alphabetical
order. Only one piece is missing.
Fix VCard

Removed "My vCard". Fixed VCard view. And actually, sorting roster makes
shit stop working, so...
Remove stuff

Removed power saving feature and mute notifications feature - nobody
uses this stuff anyway.