Add a boundsBehavior property to ScrollView similar to that of Flickable

This suggestion is to add a boundsBehavior or similarly named property to ScrollView that would behave like the property for Flickable.

ScrollView behavies similarly to Flickable already defaulting with the bounce on hitting bounds.

There is a workaround to put a Flickable as a child for the ScrollView to achieve this effect but that is not very intuitive and feels excessive for what could be achieved with a single property.