Dependent Resource MVP Scope

[csviri]

This is an umbrella issue, that defines the scope of the initial release / minimal viable product of Dependent Resources:

• Updated Docs Regarding Dependent Resources #978
• Prepare WebPage sample variants with low level API and the Dependent Resources #977
• Cleanup code and add missing unit and integration tests
• Need to review usage of DependentResource.resourceType #939
• Smart Comparing Specs To Check If Dependent Resource Needs to Applied Again #920
• Always return the up to date resource by getResource(primary) after create or update in K8S Dependent Resources #924
• Figure out whether we can avoid returning Optional for DependentResource.eventSource #938
• Check if it's possible to avoid creating the desired state if not needed (in particular, can we do the matching based only on the primary resource state instead of creating the desired state to compare it with the actual state)
• owned state needs to be configured in KubernetesDependentResource. This was previously handled by KubernetesDependentResourceController but removing the logic from there where the configuration is available now makes it awkward to do (and is actually not done).
• Review how configuration is injected in DependentResource #940
• KubernetesDependentResource should preserve metadata on updates (currently replace used) #948
• (Optional, although quite beneficial to show the power of the feature) Filtering Event of Informers After Watched Resource Update #870
• Make it possible to have dependents that are never created or updated #955