Add support for Packet with Terraform (#4043)

* Add support for Packet with Terraform

Co-Author: johnstudarus <john@jhlconsulting.com>

* removed advanced features to streamline

* clarifying usage

* Update README.md

provide a better test to validate things are working OK

* Update README.md

clarifying what to set

* minor wordsmithing

* Fix admin cert path

* clarifying how to configure keys

* enabling kubeconfig_localhost

pull over the configuration file via playbooks rather than the key files individually

* Create output.tf

* Add support for node specific plans

contrib/terraform/packet/variables.tf

@@ -0,0 +1,56 @@
+variable "cluster_name" {
+  default = "kubespray"
+}
+
+variable "packet_project_id" {
+  description = "Your Packet project ID. See https://support.packet.com/kb/articles/api-integrations"
+}
+
+variable "operating_system" {
+  default = "ubuntu_16_04"
+}
+
+variable "public_key_path" {
+  description = "The path of the ssh pub key"
+  default     = "~/.ssh/id_rsa.pub"
+}
+
+variable "billing_cycle" {
+  default = "hourly"
+}
+
+variable "facility" {
+  default = "dfw2"
+}
+
+variable "plan_k8s_masters" {
+  default = "c2.medium.x86"
+}
+
+variable "plan_k8s_masters_no_etcd" {
+  default = "c2.medium.x86"
+}
+
+variable "plan_etcd" {
+  default = "c2.medium.x86"
+}
+
+variable "plan_k8s_nodes" {
+  default = "c2.medium.x86"
+}
+
+variable "number_of_k8s_masters" {
+  default = 0
+}
+
+variable "number_of_k8s_masters_no_etcd" {
+  default = 0
+}
+
+variable "number_of_etcd" {
+  default = 0
+}
+
+variable "number_of_k8s_nodes" {
+  default = 0
+}