SwappableCell: move drag registration to setControlView
Launchpad: add method for getting the cell at a fiven point
Launchpad: implement draggingUpdated
Launchpad: checking animation layers is a much better test!
Launchpad: when adding cells from non-mai thread we need to fluch implicit animations
launchpad: disable certain implicit animations for the cell layers.

specifically we dont want fade in/out