Improve table.move documentation

[metatablecat]

Changes

The existing documentation is fairly vague about how move operates, this clarifies the behaviour in an easier to understand manner.

Note: i'm unsure if the ending index in dst is actually t + (b - a), will edit if not the case.

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[metatablecat]

Note: i'm unsure if the ending index in dst is actually t + (b - a), will edit if not the case.

It is, proved it in a notepad document.