Update helpers documentation

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

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

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

Start by reading the existing helpers documentation and locating the controller configuration and sorting entry points. Determine where the new enable_sorting option belongs and verify that its default is false; the work is done when controller sorting is supported and the helpers documentation describes the option.

Written by the indexing model from the issue text.