Change NetCDF.inc headers to correct ones

Automatically change the headers from 'NetCDF.inc' to 'netcdf.inc'

grep NetCDF.inc *
libUN_mod.f90:    INCLUDE 'NetCDF.inc'
outice.f90:    INCLUDE 'NetCDF.inc'
sbcnew.f90:    INCLUDE 'NetCDF.inc'