parallels: reimplement functions, which change domain state

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>