Register release (packages) in artifact-store/repository.

def register_packages(ctx, repo=None, dry_run=False):
    """Register release (packages) in artifact-store/repository."""
    original_ctx = ctx
    if repo is None:
        repo = ctx.project.repo or "pypi"
    if dry_run:
        ctx = DryRunContext(ctx)

    packages = ensure_packages_exist(original_ctx)
    print_packages(packages)
    for artifact in packages:
        ctx.run("twine register --repository={repo} {artifact}".format(
                artifact=artifact, repo=repo))