Add TODO to installation docs

docs/install.md

@@ -72,3 +72,5 @@ Each installation of VIPSWeb can be customized in several ways
 
 This is done by making a copy of `local_settings_sample.py` to `local_settings.py` and customizing it. `local_settings.py` is ignored by Git.
 
+## Configuration of VIPSLogic
+TODO
\ No newline at end of file