Why does the N5CloudImageLoader require an N5Reader instance

[StephanPreibisch]

Hi @tpietzsch,

it is confusing to me why the N5CloudImageLoader requires an N5Reader instance. It is nice to be able to provide it, but it shouldn't be necessary as far as I saw from the code, correct?

Specifically, when I am saving the N5 to a new place on e.g. S3, I want to close the N5Writer instance to ensure everything is closed, rather than having to give that instance to the N5CloudImageLoader. I could open it for reading, but it should be able to do that by itself.

What do you think?

Thanks, Steffi