Add test cases to cover EJB client clustered session creation

EJB client session creation involves creating a proxy for a SFSB deployed on a remote server, which has the side effect of creating a session instance on the chosen target node.

Whether or not the operation is successful depends on three factors:

• the connections defined in the EJB client configuration
• the server environment in which the client is executing
• any strong affinity set by the client

These tests consider session creation in a clustered environment. The default server environment is a cluster called "ejb" with two nodes, "node-0" and "node-1".

The following test scenarios are covered:
1. "normal" scenario

• client configuration: points to node-0
• server environment: module deployed on cluster "ejb" = {node-0, node-1}
  
  2. "failover" scenario
  * client configuration: points to node-0
  * server environment: module deployed on cluster "ejb" = {node-1}
  
  3. "bad connection" scenario
  * client configuration: points to node-2 (non-existent)
  * server environment: module deployed on cluster "ejb" = {node-0, node-1}

As mentioned earlier, these tests operate in a single two-node cluster environment. A third singleton, non-clustered node added to the available environment would permit more complex scenarios (where we could test cluster affinity specification more directly).