Turnkey Image Factory - Slave Appliance

The slave appliance is based on the tkldev appliance, buildbot 0.8.6p1
and Debian wheezy.

Appliance description:
 * Based on tkldev.
 * Comes with outscale-image-factory tools and its dependencies.
 * Runs a buildbot slave process in an EC2 cloud. The slave is
   autoconfigured by the master.

Technical notes:
 * The buildbot slave process runs as root because the Turnkey build
   process needs root AFAIK.