public OverrideValue<String> getDatabaseOverrideValue() {
        return databaseOverrideValue;
    }
@return The cluster wide value set in the UI and stored in the database, if present.
If no database override value has been set an exception will be thrown.
Test with hasDatabaseOverride() first.
stroom-core-shared/src/main/java/stroom/config/global/shared/ConfigProperty.java