Adding Window Shops as a GC category

[Tatianaabor]

It may be helpful to add 'Window Shops' as a Grandchild category under Outdoor_Urban Panels.

There is an increased number of outdoor facing screens installed in windows of different retailers (i.e., screens at convenience stores, beauty salons, coffee shops, dentist offices, etc.), these are mainly reaching vehicles and pedestrians, therefore, their audience is much broader than the one being captured by their indoor screens.