code: public static WritableIntegerDataStore makeIntegerStorage(DBIDs ids, int hints) {
      return DataStoreFactory.FACTORY.makeIntegerStorage(ids, hints);
    }
docs: Make a new storage, to associate the given ids with an object of class
  dataclass.
  
  @param ids DBIDs to store data for
  @param hints Hints for the storage manager
  @return new data store