added lber_types.h.nt, lber_types.h.in
removal of NULLxxx internal macros (in favor of NULL).
ch_free added to slapd,slurpd/ch_malloc.c
#define free ch_free (should be removed after s/free/ch_free/g) in proto-slap.h
ch_malloc and friends use ber_memalloc and friends