webadmin: add vertical split table

Similar to HorizontalSplitTable but the excluded items table is located
to the left of the included items table and there are left and right
arrows which are used to pass items between the two.

Change-Id: I353c7c0fbc1461d8c8832dcd558f84f011fe37b6
Signed-off-by: Arik Hadas <ahadas@redhat.com>