public Map<String, RefDataOffHeapStore> getFeedNameToStoreMap() {
        return Collections.unmodifiableMap(feedNameToStoreMap);
    }
Get all ref stores keyed by feed name

@return Map of feedName => {@link RefDataOffHeapStore}
stroom-pipeline/src/main/java/stroom/pipeline/refdata/store/offheapstore/DelegatingRefDataOffHeapStore.java