Initial commit of pxeboot role

- iPXE menu that can be chainloaded
- Memtest and Ubuntu 18.04 targets
- preseed created on a per-serial basis

Change-Id: I6f231ad615025c50963110945a06378936ecf26f
diff --git a/vars/Debian.yml b/vars/Debian.yml
new file mode 100644
index 0000000..526c610
--- /dev/null
+++ b/vars/Debian.yml
@@ -0,0 +1,11 @@
+---
+# pxeboot vars/Debian.yml
+#
+# SPDX-FileCopyrightText: © 2020 Open Networking Foundation <support@opennetworking.org>
+# SPDX-License-Identifier: Apache-2.0
+#
+# NOTE: Only put platform/OS-specific variables in this file.
+# Put all other variables in the 'defaults/main.yml' file.
+
+pxeboot_username: "root"
+pxeboot_groupname: "www-data"