Search: escape " when sending to sphinx
tag pages should be ordered by created_at, not hotness
fade out downvoted comments less dramatically
Sponge: keep user-supplied headers separate

when doing redirections, continue with the user-supplied headers,
not the ones we've been accumulating

fixes the problem of sending the wrong Host header to a redirection
change story downvoting to be called "flag", but still count as a downvote

been in production for a while
Story: return true from recalculate_all_hotnesses!

this is usually called from the console, and true is better than a
giant array of every Story object
for direct-comment links, just use an anchor instead of js to scroll

closes #156