Switch to qemu from vmware; enhance tests

- VMware didn't do as well headless as I would have liked, and ESX
  was a bit too large of a hammer, so we switch to QEMU.
- Change the logic to simply bootstrap the stage2 installer rather
  then writing out our own preseed.
- Log to a uniquely generated log file
- Break testing out into 3 stages (networking, installer,
  final working machine).
Add a crontab and wrapper script

- Check in a copy of the crontab in use and the wrapper script
  used to test all 3 cluster machine types.