Commit Briefs
use UTC for times in listings
The listings (index pages and thread pages) now use UTC for the time to make it less ambiguous. The mail page instead keeps the local time of the sender, but there we show the full header so it's easy to see to which TZ is relative.
better gzip invocation that actually re-compress the files
most files don't change once generated, but the index pages change at every run and the thread page sometimes too, so they ought to be re-compressed.