fixed rabbitmq-plugin home environment variable requirement. This breaks as puppet does not pass on any environment variables on execution and we cannot explicitly declare it due to code flow.
added rabbitmq_exchange resource type and provider to allow us to manage exchanges. This is an initial implementation
Merge pull request #1 from hubspotdevops/rabbitmq_plugin_HOME_fix

- fixed rabbitmq-plugin home environment variable requirement.
- add rabbitmq_exchange provider type.