[RFH/PATCH 0/4] git http tests with apache 2.4

[Jeff King <peff@peff.net>]

Apache 2.4 recently shipped in Debian unstable, and I noticed that all
of the git httpd tests stopped working. It turns out that some
configuration directives have changed between 2.2 and 2.4, and the httpd
server would not start at all.

With this series, the tests run again (for me, at least). The
"<IfVersion>" checks hopefully mean that there are no regressions for
people running 2.2 and lower.

However, the final patch is very unsatisfactory. We have to pick an MPM
module to mention in the config, but we don't have any idea what's
available. I suspect what I have provided will work on most Unix-ish
systems. Under Windows, there is a totally different MPM. But I am not
sure that our http tests run at all on Windows, as we seem to check in
lib-httpd.sh for a Unix-ish apache module path.

As far as I know, Apache does not have a "try to load this module and
fallback" directive. We could perhaps look in the module directory and
try to do something clever in the shell before starting Apache. Advice
from Apache gurus is welcome.

  [1/4]: t/lib-httpd/apache.conf: do not use LockFile in apache >= 2.4
  [2/4]: t/lib-httpd/apache.conf: load extra auth modules in apache 2.4
  [3/4]: t/lib-httpd/apache.conf: load compat access module in apache 2.4
  [4/4]: t/lib-httpd/apache.conf: configure an MPM module for apache 2.4

-Peff