add support for "metadata" api resources

[wlan0]

@ublubu can you document what's done and what's missing from this list?

[ublubu]

admissionregistration.v1alpha1

• [ ] ExternalAdmissionHookConfiguration
• [ ] InitializerConfiguration

apps.v1beta2

• [x] ControllerRevision

apiextensions.v1beta1

• [x] CustomResourceDefinition

autoscaling.v1

• [x] HorizontalPodAutoscaler

core.v1

• [x] Event
• [x] LimitRange
• [ ] PodTemplate

policy.v1beta1

• [x] PodDisruptionBudget

scheduling.v1alpha1

• [ ] PriorityClass

settings.v1alpha1

• [x] PodPreset

extensions.v1beta1

• [x] PodSecurityPolicy