List existing roles

def list_roles():
    """ List existing roles """
    click.echo(green('\nListing roles:'))
    click.echo(green('-' * 40))
    with get_app().app_context():
        roles = Role.query.all()
        if not roles:
            click.echo(red('No roles found'))
            return

        for index,role in enumerate(roles):
            click.echo('{}. {}: {}'.format(
                index + 1,
                yellow(role.handle),
                role.title
            ))

    click.echo()