Allow EJB3 testsuite to have JGroups send/receive via a different interface than other services

Allow the testsuite to do the equivalent to this for clustered tests:

./run.sh -c node0 -b localhost -Djgroups.bind_addr=10.xx.xx.xx
./run.sh -c node1 -b 10.xx.xx.xx -Djgroups.bind_addr=10.xx.xx.xx

The non-clustering portion of the EJB3 testsuite has problems if node0 does not use -b localhost. On some test servers, we're finding troubles multicasting between lo and ethX, causing issues with the clustering tests. The intent here is to allow JGroups on both nodes to send/receive via the interface where multicast works.

The value passed to -Djgroups.bind_addr is set via ant property node0.jgroups.bind_addr and node1.jgroups.bind_addr. If not explicitly set, by default the former is equal to ${node0} and the latter is equal to ${node1}. That is, by default JGroups will use the same interface as is passed to -b, the same behavior as before this change is made.