Add gimie Dockerfile

[martinfontanet]

This PR adds a Dockerfile for gimie and a GitHub workflow to push new releases to the container registry.

Here is an execution example:

$ make docker-build
$ sudo docker run gimie --version
gimie 0.2.0

You can execute the command from the container using any of the two following syntaxes:

• docker run [GIMIE_IMAGE] [ARGUMENTS]
• docker run [GIMIE_IMAGE] gimie [ARGUMENTS]

I have not tested the CI/CD part yet. I only wrote it following the instructions from the GitHub documentation to publish docker images.

[cmdoret]

Looks good to me!
One small comment:
Should we name our (GitHub) releases, e.g. "0.2.0" instead of "v0.2.0"? Asking because the image tags don't have the "v". But apparently v0.2.0 is not semver-compatible, so it might be better to just not drop the v.

[martinfontanet]

Looks good to me! One small comment: Should we name our (GitHub) releases, e.g. "0.2.0" instead of "v0.2.0"? Asking because the image tags don't have the "v". But apparently v0.2.0 is not semver-compatible, so it might be better to just not drop the v.

I agree. I think we should drop the "v".