Log Message:
Update to 1.6.0.0

Some new features/corrections include:
* new addresses IP-DATAGRAM and UDP-DATAGRAM allow versatile broadcast
  and multicast modes
* range option supports form address:mask with IPv4
* changed behaviour of SSL-LISTEN to require and verify client
  certificate per default
* filan (and socat -D) could hang when a socket was involved

See: http://www.dest-unreach.org/socat/doc/CHANGES for all the details