* CI/CircleCI: Push docker images to DockerHub Push docker image to DockerHub is DOCKERHUB_PUSH_IMAGES environmental variable is set to "TRUE". * Build in Release only if pushing the images to dockerhub * Move branch from repository name to tag name * Update docker readme Co-authored-by: Trond B. Krokli <[email protected]> (cherry picked from commit 84ad438d15cffd7dca0e67d540cd41946b946bed)