Create pretty printer for job executor

[jonesmz]

E.g. see this console garbage

running jobs [(<Popen: returncode: None args: ['/home/jenkins/workspace/GenPi64_Build.Dist_...>, 'downloadstage3')]

Which comes from

def checkjob(jobs):
  print("running jobs",jobs)
  onefinished=False
  name = None
.........

This could be improved greatly to reduce nonsense output.