[machine-controller-manager]

Most notable changes

[USER] Support for Spot Instances is available in AWS driver. If the spotPrice is empty, price is automatically set to the on-demand price so that Spot instance can launch immediately. (#481, @zuzzas)
[OPERATOR] RBAC policies have to be updated to allow updating of node/status resources. (#492, @guydaichs)
[OPERATOR] New flag delete-migrated-machine-class is introduced. When set to true (defaulted to false), deletes any provider-specific machine class (e.g. AWSMachineClass) that has the machine.sapcloud.io/migrated annotation set on it. (#484, @prashanth26)
[DEVELOPER] Added migration logic for moving from provider-specific machine class to generic machine classes in out of tree code path. On migration, the machine.sapcloud.io/migrated annotation set on the old machine class. (#484, @prashanth26)
[DEVELOPER] The machine controller adds finalizer only when machine reference is present, deletes it otherwise. (#484, @prashanth26)

[USER] Retry when secret is referred by machineClass is missing (#495, @AxiomSamarth)
[USER] Node condition is added to the status of terminating nodes indicating the termination start time and reason (Unhealthy|ScaleDown) (#492, @guydaichs)
[OPERATOR] All nodes under machine deployments being rolled-out are annotated with cluster-autoscaler.kubernetes.io/scale-down-disabled: "True" during the period of rolling-update. (#496, @hardikdr)
[OPERATOR] A new command line flag autoscaler-scaldown-annotation-during-rollout is introduced to disable annotating the nodes with cluster-autoscaler annotation cluster-autoscaler.kubernetes.io/scale-down-disabled during rollout. (#496, @hardikdr)