Add configurability to how we extract v3 manifest properties from a record

[kirkkwang]

Prior to this commit:

The description, label, rights, and homepage properties were not configurable and relied on the methods supplied by the #record_property_builder. This made it difficult if an application uses the #abstract instead of #description to populate the summary property.

With this commit:

The above mentioned properties are configurable and fall back to its default when there is no configuration.

[kirkkwang]

Seems my attempt at adding a Co-author didn't work.. This was from pairing with Jeremy
Co-authored-by: Jeremy Friesen jeremy.n.friesen@gmail.com

[cjcolvar]

This is interesting! I think this could work.
The documentation and backwards-compatibility are great!

Before merging I think it would be good to update the README and to use the new pattern in the v2 manifest builder here:

iiif_manifest/lib/iiif_manifest/manifest_builder/record_property_builder.rb

Lines 13 to 14 in 0c014de

	manifest.label = record.to_s
	manifest.description = record.description

[cjcolvar]

This looks great! Thanks for adding this useful new feature!