Add terraform module

Terraform is used to manage the VMs on the Proxmox host `busch`.

terraform/busch/variables.tf

@@ -0,0 +1,10 @@
+variable "proxmox_api_url" {
+  description = "API URL, typically ends with `/api2/json`"
+}
+
+variable "proxmox_token_id" {
+  description = "Token ID"
+}
+variable "proxmox_token_secret" {
+  description = "Token Secret"
+}