Zarr updates

[akhanf]

A few minor updates/fixes:

1. Make the use of zipstores for final ome.zarr optional (disabled by default). The config['ome_zarr']['use_zipstore'] flag controls this now. Zipstores are not technically supported by ome-zarr (even though they work with zarr python library), so made this optional.. Made a generic rule to copy from work, so the intensive reading/writing of zarr files is still all done in localscratch if desired.. closes Make zipped outputs optional (not the default) #11
2. ome-zarr outputs had the wrong metadata for axes, using micrometers when the values were actually millimeters. This makes the axis label millimeters as well. closes Units incorrect (mm vs um) #13
3. removes any atlasreg rules, scripts, resources, since that is now done in SPIMquant (to be released soon) closes remove atlas registration rules #15