Add the favicon to Homebrew binaries and perhaps others, too

[Mikolaj]

Windows have them already, Debian should too, when it gets updated, browser has it. So other Linuxes and Homebrew are left without icons, I think. The original icons are at

https://github.com/AllureOfTheStars/media/tree/master/icon

and some other versions are here

https://github.com/AllureOfTheStars/allureofthestars.github.io

If it's too hard (e.g., on Linuxes too distro-dependent), it's not worth it, hence I mark it "easy".

[Mikolaj]

Postponing.