[Mitgcm-support] delZ in kpp

[mitgcm-support at dev.mitgcm.org]

Hello,

I would like to check-in (may be tomorrow) the few modifications 
(ini_vertical_grid + PARAMS.h + ini_parms.F)
that allows to define the vertical interface at the middle between
2 centers.

I have tested this option, seems OK, and don't want to lose it.

2 packages will not work with this new option:
kpp since it uses delZ (instead of drF)
flt for the same reason (note that there are also outbound index 
    in the same routine: flt_functions.F)

I can replace all delZ in kpp but I don't know if it is the 
right time to do it. 

See you,

Jean-Michel