@Override
    public ItemType getItemType() {
        return ItemType.EQUIV;
    }
Creates an EQUIV with the given item and a set of alternate words as children.
The new EQUIV will take connectivity, significance and weight from the given item.

@param item will be modified and added as a child
@param words set of words to create WordItems from
container-search/src/main/java/com/yahoo/prelude/query/EquivItem.java