o pkg/ptracers: Temporary fix for PTRACERS_useGMRedi & PTRACERS_useKPP   in gad_calc_rhs.F ; add few safety stops in initialisation phase.
o pkg/ptracers: Temporary fix for PTRACERS_useGMRedi & PTRACERS_useKPP
  in gad_calc_rhs.F ; add few safety stops in initialisation phase.

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