public Location getNext() {
        List<String> next = new ArrayList<String>(items);
        next.remove(0);
        return new Location(next);
    }
Returns a location object that represents the "next" step along this location path. This means removing the first
elements of this location's items and returning a new location for this sublist.

@return The next location along this path.
documentapi/src/main/java/com/yahoo/documentapi/messagebus/systemstate/rule/Location.java