Log Message:
Update dnstop to 20090128.
Based on PR 41779 by Fredrik Pettai.

Version 20090128:

I added a new feature to dnstop today that filters on "refused" \ 
response codes.
This might be useful in tracking the ongoing DNS-based DDoS attacks.

To use this new feature:

    dnstop -R -f refused eth0

Version 20080321:

The interesting changes came in a patch from Dave Plonka:

       Fixed a bug that cause dnstop to Memory fault when processing
       a DNS packet greater than PCAP_SNAPLEN (previously 1460) bytes
       in size.

       Raised PCAP_SNAPLEN to 65535 to avoid truncating large DNS
       packets.

       Eliminated unnecessary stack buffers and memcpy calls when
       handling packets.

Also some variables have been added to the Makefile at the request
of a packager so that it may be easier to customize where files are
installed, etc.