Added error checking to str2anlist; if the attr name doesn't match
any attribute or objectclass the offending attr name is displayed.

Don't use ldap_pvt_is_socket_ready() at all on Windows, it is
totally unneeded and getpeername() misbehaves on W2K.

move nadf.schema as it depends on lastModifiedBy

Small preparation for applying tighter semantics to operational attributes.

Passes last test (empty value); also passes many of the invalid DN tests if liberal parsing is allowed

fix non-printable flag detection; improve dn test (passes all but last in http://www.openldap.org/ietf/ldapbis/dn.txt)