Animate removal from Positioner?

[Michail Vourlakos]

> A shaderitem that isn't live (so keeps the rendered item seemingly around),
> use that to render the removal animation while the delegate is already deleted
> could work.

in that case the next to it and before items would ingnore it, so the 
animation would be
very strange... it needs a lot workarounds for a simple onremove 
animation this to work....