New update to DBT2 clone with automated sysbench runs

I have made an update to the DBT2 clone where I packed in all my
benchmarking support scripts.

This update adds a new script bench_prepare.sh that should be run
from the benchmark server and uses the input of 3 tarballs, the
DBT2 tarball, the sysbench tarball and a MySQL tarball. It will
automatically build all needed binaries on both the benchmark
server and on the MySQL Server machine (they could be on same
machine or on different machine).

The script only requires one parameter --default-directory where
one configuration file called autobench.conf should be placed.
This directory will also be used to house all result files,
builds and generated configuration files for all involved scripts.

The aim is to continue develop such that we can also benchmark
easily using different Linux versions.

The tarball can be downloaded from here

The script can also handle a MySQL Server which is Windows-based,
but the benchmark server cannot run Windows for the moment.