Update Configuration.md (#86)

Clarifying which local_settings.py file to use.

docs/Configuration.md

@@ -2,7 +2,11 @@
 
 A number of options are available on `cms/settings.py`. 
 
-It is advisable to override any of them by adding it to `cms/local_settings.py` . 
+It is advisable to override any of them by adding it to `local_settings.py` . 
+
+In case of a the single server installation, add to `cms/local_settings.py` .
+
+In case of a docker compose installation, add to `deploy/docker/local_settings.py` . This will automatically overwrite `cms/local_settings.py` .
 
 Any change needs restart of MediaCMS in order to take effect. So edit `cms/local_settings.py`, make a change and restart MediaCMS