Advent of Nim 2020 megathread

[PMunch]

I see my repository is already listed here :) But for those who don't follow 
the IRC/Discord/Gitter channel I am also live-streaming my attempts at solving 
the AoC every day on both 
[YouTube](https://www.youtube.com/playlist?list=PL9Yd0XwsGAqzeDak6qtp6hQ4m7Qo_XA_4)
 and [Twitch](https://twitch.tv/pmunche). Might be nice for those who are stuck 
on a task, or just wants to come along and see how I do them. Typically I 
stream right after work, around 3-4 UTC.