use new way of configuring cluster

CHANGELOG.md

terraform/modules/rke1/data.tf

terraform/modules/rke1/key.tf

terraform/modules/rke1/machines.tf

terraform/modules/rke1/network.tf

terraform/modules/rke1/nodes.tf

terraform/modules/rke1/outputs.tf

terraform/modules/rke1/rancher.tf

terraform/modules/rke1/security_group.tf

terraform/modules/rke1/templates/user_data.tmpl

terraform/modules/rke1/variables.tf