Add 'Images_Per_Well' support to Dataset_To_Plate

[will-moore]

See recent queries about adding multiple Images per Well: https://www.openmicroscopy.org/community/viewtopic.php?f=4&t=8711&p=20693, and https://www.openmicroscopy.org/community/viewtopic.php?f=6&t=8706

This PR updates the Dataset_To_Plate script to support multiple Images per Well.

To test:

• The script should work "as normal" but the Well Per Image parameter can be used to add multiple Images per Well.
• If there aren't enough images to fill the last Well, it will simply have fewer WellSamples than the other Wells.

[will-moore]

@sbesson We have a test for this script at https://github.com/ome/scripts/blob/6e9ca9bc26182a8f39448e413c74ecf93c268850/test/integration/test_util_scripts.py#L130 but it would need a fair bit more work to support the matrix of various input values for all the script parameters. Maybe I'll just add the new Images_Per_Well parameter.

[sbesson]

Thanks @will-moore. Agreed that covering the whole set of input values is outside the scope of this change and :+1: for focusing on the newly added parameter.

[will-moore]

Added test to test the Images_Per_Well parameter (and a couple of others)

[jburel]

./test/integration/test_util_scripts.py:145:9: F841 local variable 'n' is assigned to but never used
./test/integration/test_util_scripts.py:196:5: E303 too many blank lines (2)

[joshmoore]

Ah of course, thanks. That’s what I get for reviewing with whitespace off