Use goresctrl for parsing container and pod annotations related to RDT.
In practice, from the users' point of view, this patchs adds support for
a container annotation and two separate pod annotations for controlling
the RDT class of containers.
Container annotation can be used by a CRI client:
"io.kubernetes.cri.rdt-class"
Pod annotations for specifying the RDT class in the K8s pod spec level:
"rdt.resources.beta.kubernetes.io/pod"
(pod-wide default for all containers within)
"rdt.resources.beta.kubernetes.io/container.<container_name>"
(container-specific overrides)
Annotations are intended as an intermediate step before the CRI API
supports RDT.
Signed-off-by: Markus Lehtonen <markus.lehtonen@intel.com>