Comment 0 for bug 1531116

In the WATCHER_GOALS_OPTS the option is not mandatory but we always need a goal.
So we need to add required=True

https://github.com/openstack/watcher/blob/master/watcher/decision_engine/strategy/selection/default.py#L33

WATCHER_GOALS_OPTS = [
    cfg.DictOpt(
        'goals',
        default=default_goals,
        required=True,
        help='Goals used for the optimization. '
             'Maps each goal to an associated strategy (for example: '
             'BASIC_CONSOLIDATION:basic, MY_GOAL:my_strategy_1)'),
]