The policy was marked as "draft" in the document, but classified as
"standard" in the list because the deadline had expired without
objection, so it technically *was* standard.

In any case, it was implemented and now is therefore obsolete (because
it's useless to keep such an historical proposal forever).

Let's use --absolute because it is less error-prone: I originally
thought the number there was the *final* disk space. But actually,
without --absolute, it is *added* to the existing disk space. This can
lead to fairly catastrophic results if we add too much disk space, as
reverting this requires a complex backup / restore procedure of the
VM, because grow-disk doesn't support shrinking disks.

Also mention this problem in the docs.

still lots todo but it's a start

I know this might be better implemented as a TPA-RFC, logically, but
i feel we already have rough consensus on this.

The last request for a VM that came in (#40070) really demonstrated to
me the reason for this deprecation: `tekesicola` is certainly a
nice-looking name, but I have no idea what it means or why it was
picked. So it would make someone unfamiliar with the history of that
machine to actually know what it's for.