updates from HEAD

clients/tools/ldapsearch.c

doc/devel/args

doc/man/man1/ldapdelete.1

doc/man/man3/ldap_error.3

doc/man/man5/slapd-shell.5

doc/man/man5/slapd.conf.5

libraries/libldap/controls.c

libraries/libldap/dnssrv.c

libraries/libldap/error.c

libraries/libldap/extended.c

libraries/libldap/getdn.c

libraries/libldap/getentry.c

libraries/libldap/references.c

libraries/libldap/result.c

libraries/libldap/sasl.c

libraries/libldap/sort.c

libraries/libldap/sortctrl.c

libraries/libldap/url.c

libraries/libldap/vlvctrl.c

libraries/libldap_r/tpool.c