Apply netcat-cvs-20110926-UDPfix.patch (part 1)

This part fixes the broken UDP support.
Apply netcat-cvs-20110926-UDPfix.patch (part 2)

This part fixes build failures on platforms where struct in_pktinfo is
not available.
Apply netcat-cvs-20110926-UDPfix.patch (part 3)

Ignore failure to set SO_LINGER on UDP sockets.
Apply netcat-cvs-20110926-UDPfix.patch (part 4)

Issue description: "Another problem was in port enumeration and counts -
after initialization "0-0" was an initial port range, and it is
invalid."
Apply netcat-cvs-20110926-UDPfix.patch (part 5)

This part adds more debug logging.