Add better approx test

consolidated into the Operation structure. All reply parameters
are consolidated into the new SlapReply structure. Most operations
now have identical call signatures... Changes are not #ifdef'd,
revert to -r NO_SLAP_OP_BLOCKS if necessary to back out.

no normalizer, a_nvals = a_vals.

	schema engine updated (but not schema routines so things don't run yet)
	nvalues mostly populated, enough for tests 0-2 to pass
	schema routines needs lots of work
	modify/mods codes needs lots of work

Use LDAP_SLISTs instead of per-struct list management for schema structs
misc cleanup and lint removal

  to back-bdb, back-ldbm and back-sql (the latter with limitations);
- added handling of ":dn" attributes to extended rfc2254 filters
  and to matched value filter
- altered the behavior of get_mra() when a matching rule is given:
  now it checks whether it is compatible with the attribute syntax
  and, in case it is, the given mr is used.  In case of no type,
  the check is delayed when filtering

Coverted LDAP_LOG macro to use subsystem ID int values instead of string values

form Mikhail Sahalaev <M.Sahalayev@pgr.salford.ac.uk>.
Further work needed:
	add testxxx-matchedvalues
	rework ldapsearch(1) portion of patch to generalize use of options
---
Copyright 2001, Mikhail Sahalaev, All rights reserved.
This software is not subject to any license of University Of
Salford.

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