maint - add rabbitmq to rspec-system testing

This patch adds hiera configuration to configure 'rabbitmq.foo.vm' with
rabbitmq, so we have end-to-end testing there too.

To use:

    RSPEC_SET=centos-64-x64-rabbitmq rake spec:system
Merge pull request #90 from richardc/rabbitmq-rspec

maint - add rabbitmq to rspec-system testing