Add python-storyboardclient

Add the python StoryBoard client to the index page.

Change-Id: I50d1433d7ba28e6eb8c93d9b084d2bd0b567d842

docs-site/infra-documents.yaml

@@ -17,6 +17,8 @@ documents:
     directory: shade
   - name: Storyboard
     directory: storyboard
+  - name: Python StoryBoard Client
+    directory: python-storyboardclient
   - name: OpenStack CI
     directory: openstackci
   - name: Zuul