Instead of keeping a local copy of spec_helper_acceptance.rb and
requiring updates to all modules for any change, we can move it into the
common helper gem and require it from there. This will make it easier to
create and review changes that affect all puppet modules. Also change
the Gemfile to look for the gem in the local workspace if running in a
zuul environment.
Change-Id: I5c79b9661db5bec8c2de1763dc96568c9b3bba54
1619f290d7