Add alberto's suggestion on currentUser's login status to refactor.md

docs/refactor-todo.md

@@ -8,6 +8,7 @@
 queryParams of the piece_list_store should all be reflected in the url and not a single component each should manipulate the URL bar (refactor pagination, use actions and state)
 - Refactor string-templating for api_urls
 - Use classNames plugin instead of if-conditional-classes
+- Instead of using `currentUser && currentUser.email` in an validation that checks whether we user is logged in or now, in the `UserStore` on login we set a boolean property called `isLoggedIn` that can then be used instead of `email`
 
 # Refactor DONE
 - Refactor forms to generic-declarative form component ✓