Fix apt key not being a key

This prevents the key from being constantly re-added everytime puppet is run
due to apt not detecting that the key is already present.
Add rabbitmq_exchange type and provider
Allow to not manage the service (eg. for HA setup)
Update manifests/repo/rhel.pp

Avoids that RPM GPG-Key import is executed at every Puppet run.

Rabbitmq::Repo::Rhel/Exec[rpm --import http://www.rabbitmq.com/rabbitmq-signing-key-public.asc]/returns: executed successfully
Add rspec for rabbitmq_exchange type
Add rspec for rabbitmq_exchange's rabbitmqadmin provider
Specifying provider for native types is no longer necessary
Using the default-port in Docs

Why you change the port without explicitly mention it in the docs?
Update README.md

Correcting two typos in the hash key names for the RHEL configuration section.
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
Implmented rabbiqmq exchange type and provider. This version does not depend on the installation of rabbitmqadmin, but rather on the ruby gem amqp being installed.
Adds Support for Mirrored Queues within a cluster.

Prior to this patch, mirrored queues would not behave properly.
Rabbit mirrored queues had several bugs that were fixed in 2.8.7:
  https://www.rabbitmq.com/release-notes/README-2.8.7.txt

rabbitmq::repo::apt can not be used since 2.8.7 is not the latest version:
  http://www.rabbitmq.com/install-debian.html

The patch adds a new paramater [*config_mirrored_queues*] that will install
the rabbitmq-server 2.8.7 package and required dependencies when
config_cluster is true.
Merge pull request #50 from AlmirKadric/master

A few fixes and missing features
Merge pull request #48 from akandels/patch-1

Update README.md
Merge pull request #55 from danehans/master

Add support for Mirrored Queues within a Rabbit Cluster
Minor fixes to syntax so this works under 2.6.
Merge pull request #45 from empi89/patch-2

Using the default-port in Docs
Merge pull request #56 from apenney/puppet26

Minor fixes to syntax so this works under 2.6.
Merge pull request #40 from joshuatobin/docs

Specifying a provider for native types is no longer necessary