use AI_ADDRCONFIG if defined in the environment
MozNSS: update list of supported cipher suites

The updated list includes all ciphers implemented in Mozilla NSS 3.13.15
TLS: do not reuse tls_session if hostname check fails

If multiple servers are specified, the connection to the first one
succeeds, and the hostname verification fails, *tls_session is not
dropped, but reused when connecting to the second server.

This is a problem with Mozilla NSS backend because another handshake
cannot be performed on the same file descriptor. From this reason,
hostname checking was moved into ldap_int_tls_connect() before
connection error handling.
MozNSS: better file name matching for hashed CA certificate directory

CA certificate files in OpenSSL compatible CACERTDIR were loaded if the
file extension was '.0'. However the file name should be 8 letters long
certificate hash of the certificate subject name, followed by a numeric
suffix which is used to differentiate between two certificates with the
same subject name.

Wit this patch, certificate file names are matched correctly (using
regular expressions).
MozNSS: ignore certdb database type prefix when checking existence

If the certdb is specified including the database type prefix (e.g.
sql:, dbm:), the prefix has to be ignored when checking the
certificate directory existence.
MozNSS: load certificates from certdb, fallback to PEM

If TLS_CACERT pointed to a PEM file and TLS_CACERTDIR was set to NSS
certificate database, the backend assumed that the certificate is always
located in the certificate database. This assumption might be wrong.

This patch makes the library to try to load the certificate from NSS
database and fallback to PEM file if unsuccessfull.
configure: use pkg-config for Mozilla NSS library
run autoreconf

AUTOMAKE=/bin/true autoreconf --install --force
rm -rf autom4te.cache/