Make Config and Settings coherent names

[jankapunkt]

Currently we have a Config to control app-wide configurations, which itself uses settings.json as source. We should use one of the names for both.

@maliyildiz1 @turndownfawad what do you think we should use as name, settings or config?

[turndownfawad]

There are settings, options, preferences and then there is a configuration.

If it's not something users can decide to change within the app for themselves, i.e. it's meant for devs only anyway, I advise using configuration.