feat: add info command line subcommand

[ThomasFrans]

Adding an info command allows the documentation to refer to it when mentioning platform specific information. This gives users a nicer experience since they don't need to think about how ncspot will behave on their system, but can run ncspot info to get that information.

closes #1325

[ThomasFrans]

Describe your changes

• Add the info subcommand which prints platform-specific information
• Update the config module with new functions to get the path to configuration and cache directories without creating them
• Remove the proj_dirs() function from the config module in favor of these new functions
• Add a constant for the configuration file name
• Update the documentation to refer to this command
• Update the changelog

Issue ticket number and link

#1325

Checklist before requesting a review

• Documentation was updated (i.e. due to changes in keybindings, commands, etc.)
• Changelog was updated with relevant user-facing changes (eg. not dependency updates,
  not performance improvements, etc.)

[ThomasFrans]

I don't know how PRs are merged but I just now thought that maybe the PR message was used as commit message. That's why I moved the template stuff in its own comment, as that's not part of the commit message probably... I'm not sure how commit messages are created from a PR though (I know it's a setting per repo).

[ThomasFrans]

With that I think it should be finished. It's rather simple, but I wanted to keep the output easy to parse if anyone wants/needs that.

[ThomasFrans]

Quickly changed the printed format to 'NAME_OF_KEY VALUE_OF_KEY' so it can be parsed with something like cut -d' ' -f2 if needed.

[hrkfdn]

Thanks, looks good to me! And sorry for the delay, don't have a lot of time at the moment.

[ThomasFrans]

Thanks, looks good to me! And sorry for the delay, don't have a lot of time at the moment.

No problem. If you ever need help with managing issues or PRs (like reviewing PRs or sorting/organizing issues) I could always try to help.

[hrkfdn]

Thanks again, let's get it in! :)