engine: search: vms.uptime is not working

when searching for vms: vms.uptime > 01:00 we use the
TimeSpan.TotalSeconds which is always zero (we never pass the seconds
only days, hours and minutes) instead of using the
TimeSpan.TotalMilliseconds which hold the true total time.

Bug-Url: https://bugzilla.redhat.com/1005805
Change-Id: I322a253557c71888307a60e7ae685dd38d637543
Signed-off-by: Shahar Havivi <shaharh@redhat.com>