cc5d38f4b Add option to attach a python debugger if test fails (John Newbery)
Pull request description:
Adds a simple option to the test_framework to attach pdb if the test fails.
Helpful for catching and debugging intermittent failures: Run the test in a loop with this option. The first failure will cause execution to pause and nodes will be left running for interactive debugging.
@sdaftuar
Tree-SHA512: 01cfae15fa3f04ed6ec6a99fef60a6c6a59723429309e81eacd6767caf12f5758f59b337804291ecab33a38a2958f36e2b513d201bee72a2eeb207a67046f952