Publish alpine container

[6543]

• Enable build & publish of alpine docker container
• Delete outdated BUILD file
• Move Dockerfiles into subdir "docker"
• Update & format Dockerfiles
• Introduce "next" tag

close #288

[anbraten]

@6543 What about #257?

[6543]

@anbraten I'll rebase that one

[6543]

PS: added you as co-author in the squash-merge since took some parts from #257 ...

[6543]

we can do the latest is latest stable once we did release v0.15.0 else we would have to downgrade current latest witch would break installations unnecessary who did just migrate breaking changes etc ...

[anbraten]

Okay I think we could start with next and keep latest until 0.15.0 got released on master pushes as well.
I updated my suggestions accordingly.

[6543]

lgtm

[anbraten]

Okay almost. Could you add next tag to /docs/downloads with a small description on latest vs next?

[anbraten]

Ahh and we need to fix .dockerignore. Atm it pushes all files to the build context. I fixed that in #257 by only adding the dockerfile and binary to a folder used as context. see here

[6543]

Ahh and we need to fix .dockerignore. Atm it pushes all files to the build context. I fixed that in #257 by only adding the dockerfile and binary to a folder used as context. see here

I think we dont need that, it's not within the final image ...