Documentation for single interface Neutron networking with OVS

Change-Id: I7a72377f55952db629c2ce7ba4ed648635e581ef
diff --git a/doc/source/conf.py b/doc/source/conf.py
index 3e9aa45..6e3ec02 100644
--- a/doc/source/conf.py
+++ b/doc/source/conf.py
@@ -26,7 +26,7 @@
 
 # Add any Sphinx extension module names here, as strings. They can be extensions
 # coming with Sphinx (named 'sphinx.ext.*') or your custom ones.
-extensions = [ 'oslosphinx' ]
+extensions = [ 'oslosphinx', 'sphinxcontrib.blockdiag', 'sphinxcontrib.nwdiag' ]
 
 todo_include_todos = True