Revision 186

Removed variables nlm and nlp of module cv30_param_m. We do not
believe much in the benefit of these intermediary variables so we go
for clarity.

Removed variable noff of module cv30_param_m. Never used anywhere
else. Just set the value of nl explicitly in cv30_param.

Removed argument nd of cv30_param. Only called with nd = klev.

Replaced calls to zilch by array assignments. There was a strange
double call to zilch with the same arguments in cv30_mixing.

Removed procedure cv_flag. Just set the value of variable cvflag_grav
of module cvflag at declaration.