Allow assertQuerysetEqual to compare with a collection of values

[flaeppe]

It should be possible to do e.g.

self.assertQuerysetEqual(
    MyModel.objects.all(),
    [(1, timezone.now(), Decimal(1337), 1337), ...],
    transform=attrgetter("pk", "created_at", "some_decimal", "some_int", ...),
)

(Not just compare with pk's, which I think the old hints suggested?)

[sobolevn]

Thanks!