Fixes#17
There appeared to be a race condition where starting all secondary
masters all at once would cause the k3s service to fail on a number of
the other masters. A retry has been added to the task to attempt to
bring them all up until they stop failing.
Fixes#16
This is because without a CNI, nodes will never be ready and the task
will fail. You need to deploy your choice of CNI manually (such as
Calico) then check the state of the cluster using `kubectl get nodes`.