attributes read twice in N5OMEZarrImageLoader

[tischi]

in N5OMEZarrImageLoader.prepareCachedImage

there is final DatasetAttributes attributes = getDatasetAttributes(pathName);

and then in createCacheArrayLoader(), which is called within that function, it seems that the attributes are read again.

could we just pass them as an argument?!

[tischi]

In fact, it seems as if getDatasetAttributes(pathName) could be in general called much less often. Can we cache the result, e.g. for each pathName?