Change "like it" to "upvoted"
API: add upvote_ratio to Link if on permalink page
Prefs: remove some obsolete i18n strings
Prefs: fix "don't show me sites..." label
Contest mode: sort by "top" for moderators
Contest mode: support score including only upvotes

If a subreddit has the "contest_mode_upvotes_only" attribute as True
(currently must be set manually), scores while in contest mode in that
subreddit will only include upvotes.
Contest mode: add infobar to comment page