add option: -skd|-skipdir to skip some test (usefull since full list is  getting long); remove "show_help" (not used, not up-to-date, was copied from testscript ?).
add option: -skd|-skipdir to skip some test (usefull since full list is
 getting long);
remove "show_help" (not used, not up-to-date, was copied from testscript ?).

altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h