Not possible to indicate "no taints"

[dlipovetsky]

Due to kubernetes-sigs/cluster-api#707 and kubernetes/kubeadm#1358, it is not possible to indicate that a node should have no taints.

[dlipovetsky]

Since provider users want master Nodes to have no taints in order to allow Pods to be scheduled on them, I propose that users use the PreferNoSchedule taint. By using this taint, kubeadm will not set the NoSchedule taint, and Pods will be scheduled on master Nodes, unless other nodes have capacity: