Update readme.md

=============

[![test_img]][test_url]

[![gh_last_release_svg]][gh_last_release_url]

[![gh_last_release_svg]][dsm-docker-hub]

[![Docker Image Size]][dsm-docker-hub]

[![Docker Pulls Count]][dsm-docker-hub]

[test_img]: https://github.com/kroese/virtual-dsm/actions/workflows/test.yaml/badge.svg

[test_url]: https://github.com/kroese/virtual-dsm/actions

[test_img]: https://github.com/kroese/virtual-dsm/actions/workflows/test.yaml/badge.svg

[gh_last_release_svg]: https://img.shields.io/docker/v/kroese/virtual-dsm?arch=amd64&sort=date

[gh_last_release_url]: https://hub.docker.com/r/kroese/virtual-dsm

[Docker Pulls Count]: https://img.shields.io/docker/pulls/kroese/virtual-dsm.svg?style=flat

[dsm-docker-hub]: https://hub.docker.com/r/kroese/virtual-dsm

[Docker Image Size]: https://img.shields.io/docker/image-size/kroese/virtual-dsm/latest

[Docker Pulls Count]: https://img.shields.io/docker/pulls/kroese/virtual-dsm.svg?style=flat

[gh_last_release_svg]: https://img.shields.io/docker/v/kroese/virtual-dsm?arch=amd64&sort=date

A docker container of Synology DSM v7.1