frontend stuff moved into a database structure, essentially to allow overlays to be processed before database selection; passes all tests (ITS#3080)

(slapi_x_XXX is still reserved for exported functions that are not part
of the SLAPI specification)

order to prevent the operation from being passed to the backend. It
need only return a non-zero error code.

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.

and misc cleanup

	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

Support search preop/rewrite/postop plugins for root DSE and subschema

failure

Rename internal slapi_XXX API to slapi_x_XXX
Always set result code/matched/error text in operation parameter block
to make available to postoperation plugins

behaviour:

1. Plugins never return LDAP result codes, instead they return a
   small integer (0 or -1, others for special cases)
2. Preoperation plugins can abort processing by returning a non-
   zero value to the frontend
3. Postoperation plugins never abort processing (all are called)
   and their return values are ignored

Connection, Operation and Backend structures.

Ensure that SLAPI_MODIFY_MODS is set to an array of LDAPMods.

SLAPI - Netscape plugin API for slapd - based on patch contributed by Steve Omrani <somrani@us.ibm.com> as ITS#2073

inaccessible, this is original code, not contributed.)

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

ITS#1677 - cast away const warnings
ITS#1678 - unsigned char args to ctype funcs
ITS#1682 - don't redefine ldap_debug
ITS#1683 - uninitialized vars
ITS#1703 - ldo_debug initialization
ITS#1705 - unsigned testing
ITS#1706 - socklen_t args
ITS#1719 - back-tcl update (other cleanups/fixes/improvements; yet untested)
ITS#1724 - integerNormalize/integerFilter/integerIndexer bugs
ITS#1725 - libdes not required

Implement back-null (/dev/null style backend)
Cleanup some misc warnings ("%lu" format, unused/uninitialized vars,
        ambiguous operator precedence)

Kurt, please regenerate configure