one canonical url, 301 the others

[nigoroll]

saving from irc:

We respond with 200 to all permutations allowed by https?://(?:www\.)?\.varnish-cache\.org (tls or not, www or not - at least, idk if there are more urls accepted by our server)

To avoid being punished for duplicate content, we should define one primary url and 301 all others (keeping the path).

[nigoroll]

assigned to phk because he owns the server, if anyone else can look after this, please do

[bsdphk]

I'll happily share this responsibilty with anybody with more webmaster clue than me

[nigoroll]

done. As discussed with @bsdphk on irc, we will not force people to https, though