[VOL-3634] Adding multi-stack support docs

Change-Id: I290ca9b2e9ee73c96010b53493144da728377f01
diff --git a/overview/deployment_environment.rst b/overview/deployment_environment.rst
index 44f877f..45f3b9a 100644
--- a/overview/deployment_environment.rst
+++ b/overview/deployment_environment.rst
@@ -60,6 +60,7 @@
    ./lab_setup.rst
    ./pod_physical.rst
    ./dev_virtual.rst
+   ./multi-stack.rst
 
 Tooling
 -------