Co-authored-by: zeripath <art27@cantab.net>

* add warnging on docs

* fix docs

* Setup docker multi-stage and little sugar at it

* Make codacy happy ?

* Revert back to what the official docker documentation suggest

Codacy don't seems to follow https://docs.docker.com/engine/reference/builder/#maintainer-deprecated

* Update golang version

* Create docker/manifest/base.yml

serve as base for build docker image for most platform (386,amd64,arm,arm64)

* Add make task docker-multi-arch-push-manifest

To update references of a multi-arch image on docker registry.

* Use SED_INPLACE generic sed command

* Delete Dockerfile.aarch64

Delete Dockerfile.rpi

* Use gitea/gitea-base as base

and replace deprecated MAINTAINER by LABEL (https://docs.docker.com/engine/reference/builder/#maintainer-deprecated)

* Fix rebase

* Use sapk/gitea-base as base

* Split makefile for docker

* Fix version to v3.6

Could use in later version edge of alpine official library that support multi-arch for armhf.

* Remove sapk/gitea-base and use directly new official alpine multi-arch