didn't bother to acquire)...

Modify ldap_result to assert returned error is not an one reserved
for API use.
Modify frontend LDAP operation routines to return an error code.
The returned value will be used to determine if an unsolicited notification
should be sent to the client.
Need to review returned error codes.  Namely some LDAP_PROTOCOL_ERROR
will like need to be changed (as they will cause unsolicited notifications).

remove race conditions on connection close.
BROKEN: various counters for dn=monitor.
Initial testing on FreeBSD (with and without pthreads) was successfull.
Have not yet tested preemptive threading environments.
Have not built against backends other than LDBM.

Separates per backend type from per backend database initialization
	and startup.  Also supports per type / per backend shutdown.
New frontend startup/shutdown routines are also provided:
	slap_init() slap_startup() slap_shutdown() slap_destroy()
New frontend->backend startup/shutdown is managed by:
	backend_init() backend_startup() backend_shutdown backend_destroy
backend_init() now calls bi_init() to initial all function pointers
for the backend (excepting bi_init() which is now the only hardcoded
entry point).  New entry points are detailed in slap.h struct
backend_info.  backend_info is a per database type structure.
Besides the new startup/shutdown entry points, the new interface
also supports per backend type configuration options.  One could have:

	backend bdb2	(new Berkeley DB 2 backend)
	bdb2_home	/directory

	database bdb2
	...

	*** This code is fairly experimental ***
	*** Much cleanup and testing is still needed ***

see slap.h for details on struct backend_db and backend_info.

Most function and variable definitions are now preceded by its extern
definition, for error checking.  Retyped a number of functions, usually
to return void.  Fixed a number of printf format errors.

API changes (in ldap/include):
  Added avl_dup_ok, avl_prefixapply, removed ber_fatten (probably typo
  for ber_flatten), retyped ldap_sort_strcasecmp, grew lutil.h.

A number of `extern' declarations are left (some added by protoize), to
be cleaned away later.  Mostly strdup(), strcasecmp(), mktemp(), optind,
optarg, errno.