(GH-91) Update to use rspec-system-puppet 2.x

This will bring us up-to-date with the latest version of the rspec-system-*
family.

Signed-off-by: Ken Barber <ken@bob.sh>
Merge pull request #92 from kbarber/ticket/master/GH-91-rspec-system-2

(GH-91) Update to use rspec-system-puppet 2.x