core (widgets_handler): use a StencilView + BoxLayout instead of ScrollView as wrapper: The default wrapping when no Carousel or ScreenManager was used was a ScrollView. This was causing bugs as the touch event is not propagated correctly when a ScrollView is in children of ScrollView (notably causing trouble with ModernMenu on ContactList and FileSharing widgets). To avoid that, a simple StencilView with BoxLayout is now used instead. If a ScrollView is needed, it can be added inside the widget (this is the case for WidgetSelector).

f95d0c31d45558c7b3e2fc39398f51eb0190bdca 0.7.0a1
4233be74572a1af8eebd502c009a10641c63ca0c 0.7.0a3
5c28cf8815319abd8c963022091cf4726764a3e6 0.7.0b1
51f73d210da908c9fb292e6bd7fda42a9d2b8453 0.7.0