Small improvement: Add outline and/or better highlight of the selected item on wall view / grid view / coverflow

[Andrey Coutinho]

Currently, the aforementined views only highlight the currently selected game by increasing its boxart size. Depending on the color and original size and shape of boxart images you're using, this effect can be too small to notice, making it hard to distinct exactly and immediately which game is highlited. This problem is more noticeable on grid/wall view, because there are more boxarts on screen at any given time, with the one the cursor is selecting only slightly zoomed in.

Other interfaces that use grid style, like Steam Big Picture or Netflix, not only increase the size of item the cursor is at, but also add an outline around it andslightly darken unselected items, making it easier to follow and control the cursor.

Big Box already applies a cursor style highlight on some views, it just needs to become available for others