(Maint) Add vagrant setup for running acceptance tests

With this patch you can now cd to the acceptance/config/linux directory
and then "bundle install" then "bundle exec rake test" to run all of the
acceptance tests using a centos master and an ubuntu agent. All that is
needed is a working vagrant install.

There are still 2 issues with this:

  1. It depends on the internal to puppet labs fake-forge.
  2. The IP addresses are chosen statically and so can collide with other machines on a network. This results in very hard to fathom errors when communicating with the hosts.