netstat-nat

This is a reimplementation of the netstat-nat[1] tool, written
entirely in Go. It uses the same command line flags and almost the
same output format so it can be used as a drop-in replacement in most
cases.

Differences
-----------

- The original version limits the printed hostnames to fixed width. We
  do not.

- The -x flag is a NOOP because we do not limit the length of
  hostnames.

- The -N flag is not yet supported.

Links
-----

[1]: http://tweegy.nl/projects/netstat-nat/