use EXF_OPTIONS.h to set pkg/exf options except if done in ECCO_CPPOPTIONS.h   (previously, ALLOW_AUTODIFF_TAMC was controling this switch)
use EXF_OPTIONS.h to set pkg/exf options except if done in ECCO_CPPOPTIONS.h
  (previously, ALLOW_AUTODIFF_TAMC was controling this switch)

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