Initial skeleton for devstack-tempest base job

Setup the initial folder and play to run tempest.
This simply runs tempest full for now, with not support for config
options.

Change-Id: I5a76dd23900a1b5fb1764fafd837d69baf9ed8b1
Depends-on: Iffe54fbccbccd68db08f79a1b51dd7f76dbff408
diff --git a/roles/setup-tempest-data-dir/defaults/main.yaml b/roles/setup-tempest-data-dir/defaults/main.yaml
new file mode 100644
index 0000000..14265f0
--- /dev/null
+++ b/roles/setup-tempest-data-dir/defaults/main.yaml
@@ -0,0 +1 @@
+devstack_data_dir: /opt/stack/data