code: public static RequestToken fetchAll(String collection, BaasQuery.Criteria filter, int flags, BaasHandler<List<BaasDocument>> handler) {
          BaasBox box = BaasBox.getDefaultChecked();
          if (collection == null) throw new IllegalArgumentException("collection cannot be null");
          Fetch f = new Fetch(box, collection, filter, flags, handler);
          return box.submitAsync(f);
      }
docs: Asynchronously retrieves the list of documents readable to the user
  in <code>collection</code>
  
  @param collection the collection to retrieve not <code>null</code>
  @param flags {@link RequestOptions}
  @param handler    a callback to be invoked with the result of the request
  @return a {@link com.baasbox.android.RequestToken} to handle the asynchronous request