Update data documentation

**Feature request**
It would be great to have analytics for middleware.

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

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

Start by locating the middleware configuration and existing config options in the repository. Read how middleware is configured and how production metrics or analytics are currently handled, if present. Done means the requested enable_analytics option exists with a default of false and the intended middleware analytics behavior is defined and tested.

Written by the indexing model from the issue text.