code: public  <T> ESDatas<T> searchAll(String index,  int fetchSize ,Class<T> type) throws ElasticSearchException{
  		return searchAll(index,  fetchSize ,(ScrollHandler<T>) null,type);
  	}
docs: 检索索引所有数据
  @param index
  @param fetchSize
  @param type
  @param <T>
  @return
  @throws ElasticSearchException