OME-ZARR support for BigStitcher-Spark

[StephanPreibisch]

Full OME-ZARR support for export of fused volumes (except for non-rigid fusion), also now uses the fusion code from multiview-reconstruction.

Documentation is not fully done, merging now so Tobias can work on it ...

@tpietzsch @krokicki @takashi310 @mkitti

[mkitti]

I'm curious about how much of the OME part is actually implemented here as opposed to just Zarr.

[mkitti]

Os the OME version declared anywhere?

{
  ...
  "attributes": {
    "ome": {
      "version": "0.5",
      ...
    }
  }
}

[StephanPreibisch]

This is using the implementation of @bogovicj ... so it is fully implemented (except for the multi-well stuff etc). The exported volumes were tested in Fiji, Neuroglancer, Allen 3D Viewer, and the OME-NGFF validator.

This is the code that calls John's code: https://github.com/PreibischLab/multiview-reconstruction/blob/c2aa04fa9d9d562d053b1c76eb5ffcb3a9f74af9/src/main/java/net/preibisch/mvrecon/fiji/spimdata/imgloaders/OMEZarrAttibutes.java#L54-L131