Drop not needed SlaveInstanceStopComputerPartitionInstallation.

Add parameter to useradd specifying that we have daemon (system) user, not normal one.

This does not work yet.

When instance is requested in stopped state it will not have setup delivery on
casuality relation, so just use Sale Order state.

This is added for compatibility until better logging functionnality is implemented.

Those instances which are belonging to tree of archived Hosting Subscription
are expected to be in request_destroy state.

Alarm running twice per day will find and cleanup such instances.