development: deprecate tutorial on adding new system

As noted in openbmc/docs#68, the tutorial to add a new system is
becoming a bit outdated. It was never a full end to end doc to begin
with and it doesn't really fit well within a tutorial anyway.

Ideally we as a community get a full blown document describing all the
different areas a user needs to update to add a new system.

This document still has some useful information within it so
for now remove it from the official tutorial README and add a
note to it that it is no longer officially supported.

Resolves openbmc/docs#68

Change-Id: I16924b7991bc5e5a9111fdfd9a0bc18828ab4363
Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
diff --git a/development/README.md b/development/README.md
index 19493f9..7435a4c 100644
--- a/development/README.md
+++ b/development/README.md
@@ -18,12 +18,7 @@
    This shows how to modify the phosphor-webui web application and test your
    changes within QEMU.
 
-4. [Adding a New System](add-new-system.md)
-
-   This shows how to create a new meta-machine layer which is the first step to
-   add support for your machine.
-
-5. [Code Reviews Using Gerrit](gerrit-setup.md)
+4. [Code Reviews Using Gerrit](gerrit-setup.md)
 
    This shows how to setup your environment to utilize Gerrit for submitting
    your changes for code review.
diff --git a/development/add-new-system.md b/development/add-new-system.md
index 3494d4d..d6fc6fd 100644
--- a/development/add-new-system.md
+++ b/development/add-new-system.md
@@ -8,6 +8,12 @@
 
 ## Overview
 
+**Please note:** This document is no longer officially supported by the OpenBMC
+team. It still contains a lot of useful information so it has been left here.
+Ideally this guide would become a standalone document (outside of the
+development tree) and would cover all of the different areas that must
+be updated to add a new system.
+
 This document will describe the following:
 
 * Review background about Yocto and BitBake