Added prerequired_packages parameter to selectivly control additional dependencies

In my environment, we do *not* use apparmor.
It is not a strict dependency: https://github.com/docker/docker/issues/4734

I think the puppet module should reflect that. Not everyone needs Apparmor installed, and maybe they don't use cgroup-lite (we don't)

This PR makes it an input so it can be controlled.
Also it is nice to have this kind of per-distro-os logic in params.