Do not run Puppet while running tests

Instead of having a cron job on the CI machines to run puppet, make puppet runs a separate step in the CI.
There are two options:
1) let puppet be part of the normal CI run (git pull the puppet repo, run puppet, wait for it to finish)
2) create a puppet job per machine via the jenkins template. That job runs regularly or before/after each other job.

Reason: puppet may install stuff during test runs that affects tests or the other way around - machine shuts down during puppet run.