infra - Generate corefiles for hung tests

Sandhya suggested this:

What I meant was the test harness could do a gcore of processes if a test is hanging. Would that be feasible ?
We could specify which processes we need core files from.
For starters we can take sqlci and tdm_arkcmp. Sqps would give the pids.

This would have to be done in a post-build-script. Not quite sure how that script would know if it were in a hung state. Perhaps just checking if trafodion is up, or by looking for the suspect processes. In a normal job there should not be any still around.

Must also move corefile reporting to a post-build-script step.