build the xos-base image and push to local repo

Change-Id: Ic606e9d8a04e9671ddfe3cf97a2dcb532c813b64
diff --git a/roles/xos-build/defaults/main.yml b/roles/xos-build/defaults/main.yml
new file mode 100644
index 0000000..3d67ba2
--- /dev/null
+++ b/roles/xos-build/defaults/main.yml
@@ -0,0 +1,4 @@
+---
+
+xos_repo_dir: "{{ playbook_dir }}/../../orchestration/xos/containers/xos"
+docker_registry: "{{ inventory_hostname }}:5000"