Update changes/219.canada.feature

Co-authored-by: Ian Ward <ian@excess.org>

Author: JVickery-TBS

changes/219.canada.feature

@@ -1 +1,5 @@
-Added a `ckan.site_read_only` config option which disables `_create`, `_update`, `_patch`, and `_delete` actions for non-sysadmin users.
+Added a `ckan.site_read_only` config option which disables actions causing side effects,
+such as `*_create`, `*_update`, and `*_delete`, for non-sysadmin users.
+
+This setting does not prevent updates to the database from sysadmin users or updates
+that skip the action API, such as collecting page view tracking data.