Create tooling (JMX) to handle heuristic transactions

now that ISPN-272 is implemented the TM is aware about the heuristic transactions.
After TM determines such a transaction it informs the System Administrator. It's SA's job to force the rollback/commit of those pending transactions.
In order to do that he needs tooling in order to access the cluster. A solution would be JMX as described here: http://lists.jboss.org/pipermail/infinispan-dev/2011-March/007651.html

This is complementary to ISPN-272 and very important as without it transaction failure cannot be fixed.