Make dockerhub image "official"

[hydrargyrum]

The dockerhub shaarli image is not marked as "official", unlike, for example debian, which makes users wonder: "is it the right one or somebody who maliciously squatted the name?"

It would be more trustable if it were official.

[ArthurHoaro]

While I agree that it would be nice to make the Docker image official, and more trustable, it requires to publish every new tag to github.com/docker-library/official-images.

I'm not willing to add another step to our release process for now. It is already too time consuming in its current state.

Also, I don't know if it would pass the review process and be considered generally useful:

“is this image generally useful?” For example, the python Official Image is “generally useful” to the larger Python developer community, whereas an obscure text adventure game written in Python last week is not.

However, if a contributor wants to take this aspect in charge, and commit to it, it would be appreciated.