Configuration chain

[tpluscode]

Once we load an API description, it should be the default behaviour and easy to use option for implementors to cascade configuration option, bottom-up.

Given a tree structure like

<Config> kopflos:api <Api> .

<Api> ^schema:isPartOf <ResourceShape> .

<ResourceShape> kopflos:handler <ResourceHandler> .

<ResourceShape> sh:property/kopflos:handler <PropertyHandler> .

it should be easy to look up a property by traversing from leaf to root PropertyHandler -> ResourceHandler -> ResourceShape -> Api -> Config.

If a property, like kopflos:resourceLoader, is not found on one level, try higher. If the Config resource does not have a value, we might resort to a config file for fallback and finally a global default.