Revert "(QENG-188) Allow foss runs to use service scripts, take 2"

This reverts commit 577fce4dcaf4c6879157fd51777d6691eae1496d.
Merge pull request #389 from waynr/revert/qeng-188

Revert "(QENG-188) Allow foss runs to use service scripts, take 2"
(QENG-967) Disable iptables on el hosts bringup.

Also fixes bug in `disable_iptables` where per-array-element was invoking wrong
method. Looks like `disable_iptables` was originally copied from
`copy_ssh_to_root`

Also adds rspec for Beaker::Hypervisor.configure

Signed-off-by: Wayne <wayne@puppetlabs.com>