CA-141163: EN: Fail to show Single-Server Private network.

-Reverted changes of CA-109242, See: #62 
-Network tab: now to show '< None >' instead of '-' as Link Status (for pools: when the network has no PIFs; for hosts: when the network has no PIF )

Signed-off-by: Gabor Apati-Nagy <gabor.apati-nagy@citrix.com>