Update to use XDG locations everywhere

[PureTryOut]

Depends on:

• Pure-try-out's XDG config PR with changed Jenkinsfile mycroft-core#2794
• Read skills from XDG Base directory specification locations mycroft-core#2803
• Migrate installed skills file to XDG Base Directory mycroft-skills-manager#88
• Install to and read skills from the XDG home directory mycroft-skills-manager#90

Description

Updates the documentation to use XDG locations. I decided to use e.g. $HOME/.config rather than $XDG_CONFIG_DIR as most people will not have the XDG variables set, and the ones who do know what they're doing already and should realize by themselves they have to update the locations as shown.

Please check properly if I missed anything or made mistakes, this was just done using some quick grep -r and I might've misunderstood certain locations as used by e.g. Docker or the Mark 1 device.

Type of PR

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• Bugfix
• Feature implementation
• Refactor of code (without functional changes)
• Documentation improvements
• Test improvements

[krisgesling]

Thanks heaps for updating this too.

It would be good to find a way to mention the XDG variable without needing to go into an explanation about it and the default path every time. But I think you're right that for the vast majority of users the default path will be the location and it's much easier to read it like this.

I wonder if we have a dedicated page that outlines the standard paths for all Mycroft files and directories? There's not that many and it's even more simplified with this XDG shift.

[PureTryOut]

I wonder if we have a dedicated page that outlines the standard paths for all Mycroft files and directories?

Agreed. I made a simple page at docs/using-mycroft-ai/file-locations.md, please give some feedback on it (or push changes yourself, that's fine by me too) 😄