Add basic instructions for deployment of acceptance test environment.

Relates to #3.

acc-test-environment/README.md

@@ -0,0 +1,20 @@
+# Acceptance test environment
+
+This configuration creates (in Azure) the Octopus Deploy server used in Terraform acceptance tests.
+
+You can create credentials for use in tests using the [Azure cross-platform CLI](https://www.terraform.io/docs/providers/azurerm/index.html#creating-credentials-using-the-azure-cli).
+
+You'll need to supply a couple of values in `terraform.tfvars`:
+
+* `azure_subscription_id` - The Id of your Azure subscription.
+* `azure_client_id` - The client Id you created in the Azure CLI.
+* `azure_client_secret` - The client secret you created in the Azure CLI.
+* `azure_tenant_id` - The name of the Azure AD tenant that the subscription belongs to.
+
+There are also a couple of option values in `main.tf` that you can override by supplying their values in `terraform.tfvars`:
+
+* `region_name` - The name of the target region where you will be deploying the environment.  
+**Note** - the VM and the storage account _must_ be the same location.
+* `resource_group_name` - The name of the resource group where the environment will be deployed (must already exist; the configuration will not create it).
+* `storage_account_name` - The name of the Azure Storage account where VM disks (etc) will be stored.
+* `uniqueness_key` - A unique value added to resource names so that your deployment doesn't clash with other deployments.

acc-test-environment/network.tf

@@ -66,7 +66,7 @@ resource "azurerm_network_security_group" "default" {
         access                      = "Allow"
         protocol                    = "Tcp"
         source_port_range           = "*"
-        destination_port_range      = "5985"
+        destination_port_range      = "5985" # HTTP
         source_address_prefix       = "*"
         destination_address_prefix  = "*"
     }