Implement set.difference()

[Smoren]

Compares first iterable against one or more other iterables and iterates the values in array that are not present in any of the other arrays.

function *difference<T>(
    ...iterables: Array<Iterable<T> | Iterator<T>>
): Iterable<T>

Needs to be implemented:

• summary.difference()
• summary.differenceAsync()
• Stream.difference()
• AsyncStream.difference()