[ ctrace : todo ]
 - parallelize the code (send all packets at once!)
 - explain the output format in the manpage, for people writing parsers
 - add option for random (weirdo) vs. current (emulated) ping sequence id
 - figure out wtf ping id generation algos are for common implementations.
 - change 'random' and fixed values to better emulate real stacks.  maybe
   even add stack characteristic database?  if so, creating an sql std. 
   fingerprint database may be an option. this may require std. protocol
   description first.
 - improved tcp header support
 - improved data field support for udp, (some) icmp (eg: echoreply), tcp.
   default should be an emulated mode.
 - implement more protocols (#1 is igmp)
