Save bytes: rename neighbour → neighbor

[toastal]

Not only is there inconsistencies between color/colour, neighbor/neighbour, but in these JSON blobs, the extra ‘u’ takes up additional, unnecessary space on disk while not adding any clarity.

[^1]

[^1]: Please consider giving up MS GitHub or offering a non-proprietary, non-US-corporate-controlled mirror for this free software project. I wish to delete this Microsoft account in the future, but I need more projects like this to support alternative methods to send patches & contribute.