Let BigDataViewer's "Open Current Image" keep OME-Zarr pyramids and OMERO settings #161

Follow-up to #108. #150 delivered the low-hanging fruit: Plugins › OME-Zarr › Open Current OME-Zarr Image in BigDataViewer asks which of the open OME-Zarrs to show. It shows them in one BDV, multi-resolution and with their OMERO settings.

Still open: two menu entries now do almost the same thing:

• Plugins › OME-Zarr › Open Current OME-Zarr Image in BigDataViewer: this plugin, pyramid- and OMERO-aware.
• Plugins › BigDataViewer › Open Current Image: BDV Fiji. It also works on OME-Zarrs, because a PyramidalDataset is a regular image too. But it shows only the resolution level that was opened: no other levels, no channel names or contrast limits. Plugins › OME-Zarr › Open Resolution Level also cannot act on that window afterwards.

Goal agreed in #108: BDV's command handles OME-Zarrs properly, and ours is removed.

Needs a BigDataViewer change. BDV's command is bdv.ij.OpenImagePlusPlugIn in bigdataviewer_fiji.