Start iSCSI properly.

Recent iSCSI package (iscsi-initiator-utils) have different way to start
(there is no more the open-iscsi script). Also use service to start
the service properly.

Signed-off-by: Frediano Ziglio <frediano.ziglio@citrix.com>
Settle udev with proper command.

udev changed name of the command, update it
Patch from Germano Percossi.
Ignore errors from iscsiadm

Patch from Germano Percossi.
Update scsi_id call

Patch from Germano Percossi.
scsi_id syntax changed.