Refresh the state of the jobs and process any events that might have
happened while libvirt was not running.

The job state processing requires some care to figure out if a job
needs to be bumped.

For any invalid job try doing our best to cancel it.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>