Add packer template for proxy build

Add packer template code to build a proxy node

openstack/nodeimage.pkr.hcl

@@ -42,6 +42,7 @@ build {
     groups        = ["base"]
     playbook_file = "./ansible/base.yml"
     roles_path    = "./ansible/roles"
+    ansible_env_vars = ["ANSIBLE_TIMEOUT=60"]
     extra_arguments = [
       "--extra-vars", "root_ssh_key='${var.root_ssh_key}'"
     ]