Package patching - improve and enable

[Vincinator]

What would you like to be added:

As a Developer, I would like to use the package-build/build script to prepare the sources for me to exactly the state as the package-build would do in a pipeline run, and keep the sources in a folder for me so I can work on the sources to add/fix/remove patches.

Why is this needed:

This enables us to efficiently do tasks required for releases:

• fix broken patches
• backport patches
• remove patches

Additional Notes
Working in feat/prepare-patch branch.

• Adding the required logic to the --debug flag
• Writing Guide in package-build/README.md on how to use this

[Vincinator]

Related: #4
Related (not complete, needs improvements): #6
Related: #3

[Vincinator]

#21

[Vincinator]

We can already use the branch of the #21 PR. Want a proper review before we merge it, but need @nkraetzschmar to not be on penguin petrol.

Postpone review after his duty.

[Vincinator]

Done with 5a5e775