Fix formatting issues in RST files

Fixed issues found in sphinx-build of documentation files

Change-Id: I6d221f03dfe7a917800c71ca31ac6e741509b21e
Issue-ID: CCSDK-2176
Signed-off-by: Dan Timoney <dtimoney@att.com>
diff --git a/docs/conf.py b/docs/conf.py
index 8f40e8b..3b28eb7 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -12,4 +12,4 @@
 html_last_updated_fmt = '%d-%b-%y %H:%M'
 
 def setup(app):
-    app.add_stylesheet("css/ribbon_onap.css")
+    app.add_css_file("css/ribbon_onap.css")