Operator in degraded mode

Annotation

maxDegraded field can be specified not only for the whole OpenStack service but also for each individual component such as api, proxy or db, so we have to specify the annotation state.yaook.cloud/max-degradation to transfer the maxDegraded field from the specific CRD to the related Deployment, StatefulSet, DaemonSet or ConfiguredDaemonSet, because _is_ready function checks these resources and it is not possible to check the maxDegraded via ctx.parent. The reason is that the label state.yaook.cloud/component does not always match the corresponding component field in the CRD.