Instead of showing comments chronologically, group them into posts, then sort
the posts by last comment date. Reason: improved comment context delivery
makes discussion bumping possible (no matter how old it is) and discussion is
what comments are about.
Comment count is limited to 5 per post.
Pages load 1.5-2x faster
Exception trace in JSON is now represented as an array
Fixed pagination of default favorites page in user pages
Fixed thumbnail size validation for non-square thumbnails
