private ImageConfiguration addSimpleDockerfileConfig(ImageConfiguration image, File dockerfile) {
        BuildImageConfiguration buildConfig =
            new BuildImageConfiguration.Builder()
                .dockerFile(dockerfile.getPath())
                .build();
        return new ImageConfiguration.Builder(image).buildConfig(buildConfig).build();
    }
Get all volumes which are defined separately from the images

@return defined volumes
src/main/java/io/fabric8/maven/docker/AbstractDockerMojo.java