Please update the way on how to adjust addons for customer needs

[Martin-Weiss]

It seems the current way of adjusting addons is not valid as skuba automatically creates a kustomized.yaml in a temporary folder?

See https://bugzilla.suse.com/show_bug.cgi?id=1177803

We need this properly documented in 4.2.x and 4.5.x so customers understand exactly how to customize addons in a Skuba compatible way including the explanation how to deal with base yaml updates for each update.

[Martin-Weiss]

Oh - and please add also the information on how to adjust/fix what customers did wrong so far based on the wrong documentation.. Thanks!

[r0ckarong]

@innobead @jenting