The dockerignore and dockerfile have also been excluded from being moved into
docker images, saving docker layer cache busts if only those are changed.
* make .dockerignore `ncdu -X` compatible to easily inspect build context
* remove cargo-chef as it was introducing more problems than it was solving
* remove rocksdb packages
* add ca-certs in the resulting image. We need that to be able to make https
connections from container with proxy to the console.
