Copyright violation in Users/Docker_Image.rst

[jayvdb]

#470 merged a bunch of text which is from https://opensource.com/resources/what-docker (and snippets appearing in various sources such as https://github.com/kecorbin/sevt-devops-intro ?, which is unlicensed , https://opensourceforu.com/2017/10/glimpse-microservices-docker-kubernetes/ , etc), and relicenced it as AGPL per https://github.com/coala/documentation/blob/master/LICENSE . That is not legal.

[jayvdb]

I think it is/was a good idea to copy from https://opensource.com/resources/what-docker . It certainly doesnt make sense to write our own "what is docker" from scratch. The intention was good. The alternative is to only link to that resource.

Unfortunately there is a bit of work to be done to make our copy of https://opensource.com/resources/what-docker legal. We need to comply with the CC-BY-SA license that they offer. That can be done with a link to the original, attribution, and our modified version needs to be dual licensed to also be CC-BY-SA, in addition to AGPL (c.f. #483).

However, we do not need to worry about dual-licensing if we clearly only copy, and do not allow modification. This can be done by properly quoting the passage. e.g. https://opensource.com/resources/what-docker Says "...."
The layout needs to be very clear that it is an unmodified copy only, and no editing of the text is desirable.

Regarding the other sentences lifted from various sources, with only slight modifications in places due to our review process, I suggest scrapping it entirely as it will be too hard to chase down all the sources, check licensing, etc.