Trending: A new answer sorting option

With the Q&A database at StackOverflow aging this really makes a lot of sense. I find it increasingly common to need to scroll past the first 1-4 answers on a question, particularly if it's from the "early" days like back in 2010-2011.

This should also revitalize things with contributors a bit too; it actually provides motivation to go in and put yet-another-answer on that decade old question that hasn't aged well.