fix timezone processing in libvarnish

[Poul-Henning Kamp]

In message <36EBC1DF-2A1D-41FA-9A81-152FD0A87CB0 at gmail.com>, Jammy writes:

>These days, we met with some Expire headers with following format which =
>are not supported by varnish yet.
>Sun, 06 Nov 1994 08:49:37 +0000

There is no requirement to support this format, see RFC2616, section
3.3.1, and I'm not particularly keen on the multi-pass way your
patch solves it, since I have an item on my list that we should
write something faster than strftime() which does a lot of work we
don't need.

(Belive it or not, but at high loads strftime() shows up in
profiling!)

If you would like to take a stab at that, you are more than
welcome.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.