Introduced base css files for plugins

Change-Id: Ia8f1bb671c6e770c19ce196f5161e48cf88b2b2a
diff --git a/Changes b/Changes
index fad80b6..6bfcd63 100755
--- a/Changes
+++ b/Changes
@@ -1,9 +1,10 @@
-0.39 2020-07-02
+0.39 2020-08-24
         - Add information on secret file to Readme.
         - Change default API endpoint to korap.ids-mannheim.de.
         - Fix label for toggle plugins.
         - Activate plugin registry.
         - Forward 'pipe' parameter to backend.
+        - Introduce base css file for plugins.
 
         WARNING: If you relied on the former default API endpoint
           being http://localhost:9999/, this will break your