Application config write back tools

[zoe-codez]

Issue

There isn't really a way for applications to save their own configuration changes right now. It requires that the user manually change the file, which has the potential for them to do it wrong or just forget to do it at all. Some sort of functionality to dump out working application configs needs to exist

Proposed solution

Add new code API to set config variables.

Solution A: Merging configs into existing configs

Use the existing file providing configurations, and write back to that (if available). Default to ~/.config/{app} if no file based config exists

Solution B : Dynamic Configs as separate files

This may need to restructure configurations a bit in order to fulfill the request.

If the current configuration lives at ~/.config/{app} (text file), then it should be moved to ~/.config/{app}/config. New data can potentially be written to a second file there, not affecting the existing user configuration (preserving any comments at least)