- this implies that jobControl is a user-resource for OpenFOAM.
  It was previously located under $WM_PROJECT_INST_DIR/jobControl,
  but few users will have write access there.

- an unset FOAM_JOB_DIR variable is treated as "~/.OpenFOAM/jobControl",
  which can partially reduce environment clutter.

- provide argList::noJobInfo() to conveniently suppress job-info on an
  individual basis for short-running utilities (eg, foamListTimes) to
  avoid unneeded clutter.