Fix overlooked conf.py setting in flattening of Doc directory.
diff --git a/Doc/conf.py b/Doc/conf.py
index 7546c51..3bd82b1 100644
--- a/Doc/conf.py
+++ b/Doc/conf.py
@@ -68,7 +68,7 @@
 # -----------------------
 
 html_theme = 'pydoctheme'
-html_theme_path = ['tools/sphinxext']
+html_theme_path = ['tools']
 html_theme_options = {'collapsiblesidebar': True}
 
 html_short_title = '%s Documentation' % release