engine: Notify host is Up only when InitVdsOnUp succeeded

Display "State was set to Up for host XXX" notification in webadmin only
when InitVdsOnUpCommand executes successfully for host.

Change-Id: If0fab61b10bea280ca81eca74f2912b61bd58876
Bug-Url: https://bugzilla.redhat.com/1040918
Signed-off-by: Martin Perina <mperina@redhat.com>