Create inventory, setup head node

Change-Id: I4604ade8413e05178922691b39c40c1397f78234
diff --git a/inventory/templates/single-prod b/inventory/templates/single-prod
new file mode 100644
index 0000000..4fe6f8d
--- /dev/null
+++ b/inventory/templates/single-prod
@@ -0,0 +1,6 @@
+[head]
+${prod}
+
+[compute]
+
+