Description of problem:
Updates to [allow-direct-connections-only] property of cluster connection renders the configuration file for AS7 invalid. The server cannot be restarted/reloaded without manual updates to the configuration file.

The AS7 server writes the [allow-direct-connections-only] property as an XML attribute of [static-connectors] property. But the [static-connectors] and [discovery-group-name] cannot be both defined at the same time. So if the [discovery-group-name] is configured and the user updates [allow-direct-connections-only], the the two fields that should not be defined at the same time are now defined in the configuration file. 

The problem:
[discovery-group-name] is defined because the user set it non-null value, and 
[static-connectors] is defined because it has the attribute for the value of [allow-direct-connections-only]. 

This is not an RHQ plugin bug. This an AS7 bug and the only work-around until the application server is fixed is to remove [allow-direct-connections-only] property from cluster connections. 

Path of affected resources:
*/subsystem=messaging/hornetq-server=*/cluster-connection=*

How reproducible:
Every time.

Steps to Reproduce:
1. Discovery and import an AS7 standalone server
2. Find resources at the addresses mentioned above
3. Attempt to update [Allow Direct Connections Only] property
4. Update another property and save
5. Send a reload operation to the server

Expected results:
[Allow Direct Connections Only] property is not available for configuration. The configuration is updated and the server reloads successfully.