Ci tools documentation updates

[AugustasV]

Added GitHub action that would push the image into the docker hub. Right now it is configured to trigger only the master branch. Configuration is made into my docker hub account, probably would be better to switch to Github Packages?
Also wrote documentation on how to spin up local Kubernetes cluster and test things locally using DevSpace. Small README improvements.

Looking for a feedback on how to improve this PR.
Not possible to add as a reviewer, so tagging like that @pijuszczyk @pawsten

[pawsten]

Thank you for your PR but I'm not sure whether It's a good idea to bind so tightly build system with minikube on docker container driver and devspace which we don't use. Isn't it overengineering?

[pijuszczyk]

I agree with Paweł. We shouldn't bind the builds to minikube and devspace.
Regarding pushing images, I'll contact the relevant people and let you know how it could be solved.

[AugustasV]

Probably I didn't explained properly. Minikube and devspace are only used for local development and testing purposes, imitating Kubernetes cluster. Github actions building, tagging, and pushing image into docker hub.

[pijuszczyk]

Hi @AugustasV ,
First of all, sorry for taking so long. Unfortunately the topic of pushing images is still in progress and I can't point you to any solution at the moment. To go forward with this pull request, could you currently limit the scope of changes to building on Github and stash changes that require image pushing & fetching for later?

That could be achieved by sticking to the changes in c-cpp.yml (except logging in to Docker Hub and push: true) and saving other changes for later. I'll try to establish how we should handle images as soon as possible.

[AugustasV]

Sure @pijuszczyk I could do that, or maybe we should go different approach? I could use Github Packages to save Docker images here on Github. It's free for public repos https://github.com/features/packages#pricing

[pijuszczyk]

Thanks for the suggestion, we could use that. However, still first I'd need to discuss this topic. I think a conclusion could be reached sometime next week. If you don't mind waiting a little longer I'll reach you then about what can be done in this case. But if you prefer to close the pull request sooner, I'd recommend stashing the changes like I described above.