extract defaults from specific shop

[alfredbez]

It would be very helpful to be able to extract the default-values from a given shop, something like this:

php vendor/bin/oxid config:export --extract-defaults-from=1

I would expect that it does the following:

• load config for shop 1 like for the usual export
• checks which keys are set in the defaults.yaml
• overwrites the existing values in the defaults.yaml with the values from the given shop-id