alphabetize torrc options within sections

Once upon a time the man page entries were alphabetical. Then we started adding a few near the other ones when it made sense. Now it's a mishmash of alphabetical-except-when-we-decided-not-to-do-it-that-way.

We should take a step back and think about a way to organize the options into categories so it's possible to a) get a sense of what all you can configure, and b) find the thing you're looking for.