code: public static BaasResult<BaasStream> streamImageAssetSync(String id, String spec) {
          return BaasAsset.doStreamSync(id, spec, -1);
      }
docs: Synchronously streams the asset.
  
  @param id   the name of the asset to download
  @param spec a size spec to specify the resize of an image asset
  @return a {@link com.baasbox.android.BaasStream} wrapped in a result