Create Grafana dashboard, include in developer environment enhancements

Since there's custom metrics to show in Grafana which is now included in the project - a dashboard should be created and added to the `config/` directory, this will need wiring up in the [`docker-compose` file](https://github.com/DLMousey/OIDC.Core-Redux/blob/master/docker-compose.development.yml) so it's automatically added to Grafana on startup for a smooth developer experience.