v1.18: 29MAR2016

        Added USELIBPCRE to make use of regex engine
        optional.

        Added support for RFC4366 SNI and RFC7301 ALPN
        (Travis Burtrum)

        Changed connection log to include the name of the probe that
        triggered.

        Changed configuration file format: 'probe' field is
        no longer required, 'name' field can now contain
        'tls' or 'regex', with corresponding options (see
        example.cfg)
        Added 'log_level' option to each protocol, which
        allows to turn off generation of log at each
        connection.
        Added 'keepalive' option.

v1.17: 09MAR2015

        Support RFC5952-style IPv6 addresses, e.g. [::]:443.

        Transparant proxy support for FreeBSD.
        (Ruben van Staveren)

        Using -F with no argument will try
        /etc/sslh/sslh.cfg and then /etc/sslh.cfg as
        configuration files. (argument to -F can no longer
        be separated from the option by a space, e.g. must
        be -Ffoo.cfg)

        Call setgroups() before setgid() (fixes potential
        privilege escalation).
        (Lars Vogdt)

        Use portable way of getting modified time for OSX
        support.
        (Aaron Madlon-Kay)

        Example configuration for fail2ban.
        (Every Mouw)

v1.16: Hardened probes, Libcap support, IP_FREEBIND support