Decide whether to move saveAttributesIfNecessary into a SingleCustomValueSaveHandler

/**
  * To be called by service save methods for customizable implementations.
  * Iterates over all attributes and calls save on the {@link ConceptDatatype} for any dirty ones.
  *
  * @param customizable
  */
 public static void saveAttributesIfNecessary(Customizable<?> customizable) {
  // TODO decide whether we can move this into a SingleCustomValueSaveHandler instead of leaving it here to be called by each Customizable service's save method
  for (Attribute attr : customizable.getAttributes()) {
   saveIfDirty(attr);
  }
 }