Deletion processing is not entirely a factor of the target, it is more
a factor of our mode of execution (dry-run vs pre-rolling-update vs
post-rolling-update). We want to introduce that post-rolling-update
phase, so introduce the DeletionProcessingMode enum and move it from
the target to the context.
* GCE support only
* Key and secret generation
* "Direct mode" makes API calls
* "Dry run mode" previews the changes
* Terraform output (though key generation not working for master ip)
* cloud-init output (though debian image does not ship with cloud-init)