* Work with new capei provider
* Fix wksctl os to correctly handle file and flux configuration
* switch to marking workload clusters in spec
* Set up machine info pool in wksctl to pass to controller in existinginfra
* Removes the requirement for a wks-controller.yaml
  The wks controller comes from the existinginfra provider.  We no longer
  need it in the repository when creating a cluster.
* inline files in cluster manifest for integration tests
* plumb inline ssh key through PEM file processing
* set version on cluster for apply_test
* Re-enables k8s 1.16 cluster support
* Plumb Context through 'plan' steps
  Doesn't do anything different as yet, but this will be useful for
  tracing, or for cancelling a command.
* point to new version of existinginfra and allow for the new context parameter in CreateSeedNodeSetupPlan
* store correct versions in local repo
* add explicit kubernetes version to multimaster test
* pin c...