[ssl] allow to manage content of certs/keys files

Allow to use two ways of certs/keys files management:

1) via specifing a path of a file:

   ssl:
      key_file: /etc/rabbitmq/ssl/key.pem

2) via specifing a path and content of a file:

   ssl:
       key: text
       key_file: /etc/rabbitmq/ssl/key.pem

The files management via authority must be removed as an unused.

Change-Id: Icdc8783449cf8ac1283f107861564b6ad36230ec
diff --git a/metadata/service/server/cluster.yml b/metadata/service/server/cluster.yml
index c669993..e8c28a9 100644
--- a/metadata/service/server/cluster.yml
+++ b/metadata/service/server/cluster.yml
@@ -2,6 +2,7 @@
 - rabbitmq
 classes:
 - service.rabbitmq.support
+
 parameters:
   rabbitmq:
     server: