@Override
        public String toString() {
            return "Builder{" +
                   "effectiveMetas=" + effectiveMetas +
                   ", effectiveTimeToMetaMap.size=" + effectiveTimeToMetaMap.size() +
                   ", feed='" + feed + '\'' +
                   ", type='" + type + '\'' +
                   '}';
        }
Add an {@link EffectiveMeta} to this set using its metaID and effectiveTimeMs.
It will de-dup items that have the same
{@link EffectiveMeta#getEffectiveMs()}, with the winner being the one with the highest
{@link EffectiveMeta#getId()}.
stroom-meta/stroom-meta-api/src/main/java/stroom/meta/api/EffectiveMetaSet.java