toward merging with n5-imglib2 interfaces

[bogovicj]

• wip toward implementing n5-imglib2 metadata interfaces

[tischi]

@bogovicj
Thank you! This looks very interesting!
Do you envision this also to look like this here: ome/ome-ngff-java#4 ?

@joshmoore, what do you think? Do we want to have an N5 dependency in https://github.com/ome/ome-ngff-java/ ?

[joshmoore]

Do we want to have an N5 dependency in https://github.com/ome/ome-ngff-java/ ?

I was thinking that ome-ngff-java as the dumbest component would be at the start of the dependency graph.

[bogovicj]

I agree with @joshmoore , I had in mind for ome-ngff-java to have no (or minimal) dependencies.
n5 stuff could depend on it, and wrap / create what they have to from the stuff here.'

re: what I did here, Multiscales probably belongs in ome-ngff-java, but I could extend it here (or n5-imglib2 or wherever) to implement SpatialMetadataGroup, which is what this PR adds

Another example: CoordinateTransformation lives in this repo, some other repo creates imglib2 RealTransforms from them.

[tischi]

This looks great then!
Shall we merge it?