Add support for multi-host Rabbitmq config

[dhgwilliam]

cluster config to be passed as array of hashes

puppet 3 doing something weird with passing the data around, improved munging may have fixed this or we may have found a weird edge case where an array that contains a single hash [{:k => :v}] gets converted in to an array of arrays [[:k, :v]], but if it contains more than one hash [{:k => :v}, {:k => :v}], it gets passed around correctly?

[cwjohnston]

Probably better described as "Array of hashes," similar to other parameters described as "Array of strings." In the interests of disambiguation, redis_sentinels parameter description probably needs the same change.

[cwjohnston]

I think we need to (conditionally?) include Service[sensu-enterprise] here as well?

[cwjohnston]

I have noticed that with repeated runs, the cluster is considered to be changed every time, even though I haven't made any changes to that portion of the manifest:

==> sensuserver-1-001-centos: Notice: /Stage[main]/Sensu::Rabbitmq::Config/Sensu_rabbitmq_config[sensuserver-1-001.vagrant.local]/cluster: cluster changed {'host' => '127.0.0.1', 'port'
 => '5672', 'prefetch' => '1', 'user' => 'sensu', 'vhost' => '/sensu'} to '{"host"=>"sensuserver-1-001.vagrant.local", "port"=>5672, "user"=>"sensu", "password"=>"secret", "vhost"=>"/se
nsu", "prefetch"=>100, "reconnect_on_error"=>true} {"host"=>"sensuserver-1-001.vagrant.local", "port"=>5672, "user"=>"sensu", "password"=>"secret", "vhost"=>"/sensu", "prefetch"=>100, "
reconnect_on_error"=>true}'

[cwjohnston]

I believe c1c6c8c has resolved the idempotence problem I described above.

@jaxxstorm @whermann I think this change should be considered for merge 😎

Closes #527
Closes #518
Closes #485
Closes #269

[jaxxstorm]

Amazing work! Great team effort and sincere thanks to @whermann @cwjohnston @dhgwilliam 👍