Enable the pglogical extension and create the replication set in a tr…

…ansaction

This will allow us to rollback the whole process if something
bad happens while creating the replication set (like a unique
constraint error).

After this change we will no longer see the replication type as
"Remote" when we fail to cleanly create the provider node.

https://bugzilla.redhat.com/show_bug.cgi?id=1380475

lib/miq_pglogical.rb

@@ -41,9 +41,11 @@ def drop_node
   #   node and creating the replication set
   def configure_provider
     return if provider?
-    pglogical.enable
-    create_node unless node?
-    create_replication_set
+    @connection.transaction(:requires_new => true) do
+      pglogical.enable
+      create_node unless node?
+      create_replication_set
+    end
   end
 
   # Removes the replication configuration and pglogical node from the