AXFR does not pass through iodine (sounds reasonable), so we should
recommend in the README.md to keep the original dns server in front if
zone transfers are required.
Server will by default listen on both IPv4 and IPv6.
No way to only listen on one protocol right now.
Use -L to only listen on a specific v6 address.
IP address to use for raw mode is still IPv4 only.
Use -n on server to make raw mode work from IPv6 clients,
then they will get an IPv4 address from the server for raw mode.
Tunnel data is still IPv4.
"Permission to use, copy, modify, and distribute this software" is now
"Permission to use, copy, modify, and/or distribute this software".
Add license header to source files missing one.
