Adding IPv6 to teensy-ntp
I ported my NTP server [https://blog.dan.drown.org/embedded-ntp-server/] from
the stm32f407 to the Teensy 4.1
[https://forum.pjrc.com/threads/61581-Teensy-4-1-NTP-server]. Because I recently
switched from a cable modem to fiber, I wanted to use my home stratum 1 NTP
servers with my public servers in