Set hard open file limit in addition to soft limit

On Ubuntu Server, the hard limit is 4096, which is less than the
soft limit of 8192 that we're trying to use. Thus, to really use
a soft limit of 8192, we need to also boost the hard limit to
8192.
Configure apache2 not to auto-start at boot

Tests expect to be able to start their own desired http server on
Apache's configured port.
Fix MySQL connection problems by making back_log=5000 work by setting net.core.somaxconn=5000

When running tests that accessed MySQL, I was getting errors like:

BENCHMARKING Query ... [MySQL] 2013/05/23 00:57:04 packets.go:31: EOF
2013/05/23 00:57:04 Error scanning world row: driver: bad connection
exit status 1

Debugging this showed that the web server box had more connections to MySQL
than expected (i.e. netstat on the MySQL box showed 100 TCP connections, but
the web server box showed 1200). So there was some sort of TCP problem, perhaps
lost ACKs as described in http://www.evanjones.ca/tcp-stuck-connection-mystery.html .

Looking at the MySQL documentation for back_log (http://dev.mysql.com/doc/refman/5.0/en/server-system-variables.html#sysvar_back_log),
it suggests that the OS setting needs to be greater than or equal to back_log. Thus,
we need to set net.core.somaxconn as big as our back_log value.

I tried this and the connection problems went away.
Retry ActivePerl download to deal with intermittent 404s

Sometimes the ActivePerl HTTP server returns a 404 for a URL that should work,
so retry it until it works, but up to a max number of retries. And delay
a little in between.
Update vert.x download URL
Merge branch 'master' of https://github.com/MalcolmEvershed/FrameworkBenchmarks

Conflicts:
	installer.py
Disable IIS HTTP logging

Match the overall policy of the other framework benchmarks.

On my setup, this improves the requests/sec of a test like 'json' by 3-5%.
Remove unnecessary HTTP response headers

This removes:

X-AspNetMvc-Version: 4.0
X-AspNet-Version: 4.0.30319
X-Powered-By: ASP.NET

I didn't see any performance improvement, but this is probably a good idea
in case the extra bytes cause another network packet to be needed,
compared to other frameworks.
Disable support for direct access of *.cshtml/*.vbhtml to improve perf

We don't need to access URLs like this because we use MVC and URL routing.

On my setup, this improves the performance of the 'json' test by 13%.
Revert "Remove unnecessary HTTP response headers"

This reverts commit 63505706988ab84391ae40705b287be23761de1d.
Revert "Disable IIS HTTP logging"

This reverts commit c31b4dc063aab4af667962ac6689e29f13bd144c.
Increase .NET minWorkerThreads to improve CPU utilization

MinWorkerThreads controls how many threads the .NET thread pool creates
when a new burst of requests come in. Increase this to properly size the
thread pool early on and improve CPU utilization, increasing throughput.

I saw gains of 5-10% at least.
Merge branch 'performance_threads' of https://github.com/MalcolmEvershed/FrameworkBenchmarks