BHV-719: Allow Spotlight to move to controls outside scroller when 5-way moving from paging controls.

Issue
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When `spotlightPagingControls` is `true` and a 5-way move up is attempted with one of the paging controls spotted, an item in the list (vertical orientation) will be spotted, instead of a control above the list.

Fix
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The `spotlight` setting of the viewport is set to `container` so that the list items are not considered siblings when calculating nearest neighbors for the paging controls.

Enyo-DCO-1.1-Signed-off-by: Aaron Tam <aaron.tam@lge.com>