library use:
LBER_ macros expand to system routines.
LDAP_ macros expand to new ber_ allocators.
Add ber_ and ldap_ memory allocators/deallocator:
ber_ routines are wrappers of LBER_ macros.
ldap_ routines are wrappers of ber_ routines.
Removed safe_realloc() macro from various files. This issue
(if an issue) should be resolved across whole package.
ldapmodify.c now uses ber_ allocators to resolve ber_bvfree()
vs. WIN32 multiple heaps issue.
These changes should facilate implementation of
ber_set_option( NULL, LBER_OPT_MEMORY_FN, ...)
and
ldap_set_option( NULL, LDAP_OPT_MEMORY_FN, ...).
