*Changed default for KPP_BEFORE_KAPPA_SHEAR

- In NOAA-GFDL/MOM6-examples#47 @StephenGriffies notes that answers significantly
  when removing the code that removed and then added back diffusivity due to
  the Jackson et al. scheme (kappa-shear). The answer changes have nothing to do
  with the removal of the code but is solely due to the round-off differences
  associated with adding and subtracting a number.

  To record this, I am changing the default to not make the Kappa-Shear adjustment
  so that the code change in #219 does not get associated with the answer changes.

src/parameterizations/vertical/MOM_diabatic_driver.F90

@@ -1562,7 +1562,7 @@ subroutine diabatic_driver_init(Time, G, param_file, useALEalgorithm, diag, &
     if (CS%use_kappa_shear) &
       call get_param(param_file, mod, "KPP_BEFORE_KAPPA_SHEAR", CS%matchKPPwithoutKappaShear, &
                  "If true, KPP matches interior diffusivity that EXCLUDES any\n"// &
-                 "diffusivity from kappa-shear.", default=.true.)
+                 "diffusivity from kappa-shear.", default=.false.)
   endif
 
   call get_param(param_file, mod, "SALT_REJECT_BELOW_ML", CS%salt_reject_below_ML, &