Add unit tests for routes

**Feature request**
It would be great to have sorting for routes.

**Use case**
Many users need this functionality for production deployments.

**Implementation idea**
Add a new config option `enable_sorting` with default `false`.

Start by locating the route handling, configuration parsing for enable_sorting, and existing unit-test patterns. Add tests showing that sorting is disabled by default and that routes are sorted when the option is enabled; done means the new behavior is covered without changing the default.

Written by the indexing model from the issue text.