Bisect points to http caching

[Matt Mackall]

I just bisected some weird behavior in hgweb where I was getting
partial/mangled pages and/or styling and found this:

The first bad revision is:
changeset:   12183:f64b416b0ac8
user:        Dirkjan Ochtman <dirkjan at ochtman.nl>
date:        Wed Sep 08 15:23:48 2010 +0200
summary:     hgweb: support very simple caching model (issue1845)

Sticking a return as the first line of caching() fixes the problem. The
server is single-repo hgweb under Apache2 mod_wsgi and possibly under a
WSGI server Augie's running called "spawning". But the bad behavior
doesn't seem to appear under hg serve. 

-- 
Mathematics is the supreme nostalgia of our time.