Also update consistency checking.

connection_xml was not correctly validated.
connection_xml and sla_xml are optional, so their dict can evaluate to None or {},
which is False.

Subscription movements are not built for now.

But whenever it is set, it shall be correct XML.

By registering noop activity on alarm itself which depends on tag used in alarm
only one alarm will be run in same time.

slap_interaction_workflow has already global scope of interaction, so keep it
like this and do not add yet another workflow to do one interaction.

Some Software and Slave instances can have too old clenaup deliveries.

Any correct XML is accepted, even if as dict it evaluated to false, so if call
to getInstanceXmlAsDict succeed evaluate expression to true.

Whenever it is changed, all related delivery lines have to be reindexed, as
this impacts software_release table.

Provide updated revision files.

There is no need to get the root software instance, as the hosting subscription already contains the needed information

It might happen that something else is newer then cleanup delivery (eg. because
of user was able to ask to stop/start just after cleanup).

So clone currently waiting cleanup delivery with date newer then previous one
and replace it. Thanks to this instance destruction will be possible.