This will let a non-shared Theia (for example coming from shacache
binary) to be able to use the shared parts of a machine.

See merge request nexedi/slapos!1409

See merge request nexedi/slapos!1407

See merge request nexedi/slapos!1399

Fix takoever of a theia with initial embedded instance. The issue was
that the promise checking that the embedded instance was successfully
requested relied on files which were not transferred to backup theia.

The location of these files has been changed in order to transfer them;
therefore the old location is still checked for upgrade-compatibility.

Test that takeover of theia with an initial embedded instance succeeds.

See merge request nexedi/slapos!1403

Now each partiton in slapos-sr-testing has its own IPv6 thanks to
ipv6 range, takeover url changes after takoever, so up-to-date
connection parameters need to be fetched before doing a second
takeover.

restart restic after renewing certificate, using the same approach as
software/dufs

Because dufs only reads certificate on startup it does not detect when
the certificate was renewed.

The only thing supported by dufs is to restart, so we use hash-files
options of wrapper recipe to

Resiliency import script had a race condition where the proxy might not
have finished restarting before formatting the partitions, causing the
import script to randomly fail during format because the proxy is down
when format tries to send it updated computer information.

See merge request nexedi/slapos!1406