Parameter type "ConfigMapName" and "SecretName"

[ANeumann82]

What would you like to be added: Two new parameter types, "ConfigMapName" and "SecretName". These would generally be strings, but KUDO can have additional functionality:

• Verify that the resources in those parameters exist in the namespace the operator instance is deployed.
• Add an finalizer to prevent the resource to be deleted as long as the operator is running (this might interfere with updates to the resources though?)

Why is this needed: Operators often define parameters that the user should set to the name of an existing secret or config map. To prevent typos, KUDO could check if the requested resource actually exists and error out on install/update very early.