Add controls to extended ops API signatures, need impl.
Update password to support optional server side generation of
new password, verification of old password, and changing of
non-bound user's passwords.

On Windows, WSAENOTSOCK is treated the same as EBADF.  This is needed because of a race condition (sock is selected just after another thread closes it), which needs a proper fix.

frontend to complete parsing of extended op reqdata.
Modify password extended operation to allow optional id (DN)
entry to change (not tested).  Also, provide room to allow
server side password generation (not implemented).  Added optional old
password field to support proxying (not implemented).
Need to implement replog() support.

Relocated modify struct to be next to other structs.

Rework lutil_passwd routines to use struct berval instead of strings.

Reported by tsarna@endicor.com

referral URL is not a '/'. Also in send_search_reference, corrected the
comparison for the pre-V3 case. Previously, referrals were being dropped
completely for V2 subtree searches. More work is still needed, V2 onelevel
referral handling is wrong.

"ldap://host".

user password.  Likely to be modified to use bind control
instead.  Use of modify deprecated in favor mechanisms that
support passwords stored externally to the directory (such
as in a SASL service).
Modified slapd extended operation infrastructure to support
backend provided extended operations.

Changes for URI spport:  New routines ldap_initialize and ldap_create; LDAPURLDesc replaces LDAPServer, LDAPURLDesc list used instead of ldo_defhost.

Changes for URI spport:  New routines ldap_initialize and ldap_create; LDAPURLDesc replaces LDAPServer, LDAPURLDesc list used instead of ldo_defhost.

Changes for URI spport:  New routines ldap_initialize and ldap_create; LDAPURLDesc replaces LDAPServer, LDAPURLDesc list used instead of ldo_defhost.

Changed ldap_pvt_tls_init_def_ctx() to not fail if there is no cacertfile/dir specified.  This lets LDAP_OPT_X_TLS_REQUIRE_CERT=0 work.  If LDAP_OPT_X_TLS_REQUIRE_CERT=1, connection will fail as appropriate since there is no CA list.