parallels: reimplement functions, which change domain state
    
    Change domain state using parallels SDK functions instead of
    prlctl command.
    
    We don't need to send events from these functions now, becase
    events handler will send them. But we still need to update
    virDomainObj in privconn->domains.
    
    Signed-off-by: Dmitry Guryanov <dguryanov@parallels.com>