Allow jconsole to be attached to testsuite

JConsole (http://java.sun.com/developer/technicalArticles/J2SE/jconsole.html) is an useful tool to look for memory leaks and generally for monitoring the use of resources. We should allow uses to attach jconsole to the testsuite (thus client side), as providing the -Dcom.sun.management.jmxremote sysprop on command line mvn is not enough.

(please note I've already added the prop inadvertently in jbws native, this need to be configurable though)