.osx: read and print defaults before/after a change

Hi,
it would be great if we could log what change is being made when the script runs; kind of a log.
I've created the repo with a script that will read values: https://github.com/dnozay/osx-defaults
Usually reading the value does not require `sudo`. Could be useful as a submodule maybe?

Start by reading the repository's .osx script and the referenced dnozay/osx-defaults project to understand how defaults are currently changed and read. Define the logging scope, including the before-and-after values, and consider whether the external project should be integrated; done means changes are clearly reported when the script runs.

Written by the indexing model from the issue text.