Use XDG_CONFIG_HOME on MacOS

[cideM]

I don't have data on this but I am pretty sure that most people place scripts in unix style directories rather than /Library. As such, quite a few people probably use XDG_CONFIG_HOME even on MacOS. Yet this library doesn't support that, which means every CLI app relying on this library also doesn't (jesseduffield/lazygit#641)

[wakatara]

Yeah, I am just looking at this library now and trying to figure out how to override that. I think there should be the option for override for OSX apps. Definitely CLI apps want to be going in the XDG_CONFIG_HOME.

Course, I was planning on trying to just override this with an if XDG || Darwin {config.XDG} type thingy. Still looking into how to easily do that, but yes, I agree with the override (or instructions on how we should be doing it "canonically" with the lib.

[raine]

/Library/Application Support doesn't appear standard at all for CLI tools.

I don't have a single CLI tool with configuration there.