Changed range for valid packets since some DNS packets can have an ID of 0

I've seen this raise an exception when valid DNS packets come in that have an ID of 0. According to RFC1035, it looks like the ID must be a 16 bit identifier, which can include 0.  I just simple changed the range check for valid IDs from 1..65535 to 0..65535 which should fix when an ID of 0 is used.

If you have any questions please let me know, hope this helps!

Jason