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/acl-devstack-files/README.rst b/roles/acl-devstack-files/README.rst
new file mode 100644
index 0000000..76e7e58
--- /dev/null
+++ b/roles/acl-devstack-files/README.rst
@@ -0,0 +1,10 @@
+Grant global read access to devstack `files` folder.
+
+This is handy to grant the `tempest` user access to VM images for testing.
+
+**Role Variables**
+
+.. zuul:rolevar:: devstack_data_dir
+   :default: /opt/stack/data
+
+   The devstack data directory.