Gk browser drag reorder array

Possible to drag array items to reorder. Animated.

Requires change in bindings

https://app.asana.com/0/15028213105325/13316669162245
Because that is how move(source, dest) works, it moves an object from source index to dest index as seen BEFORE removing the object. There are arguments for and against this set up, but since that's the way it works in the core it might make sense to use it in the bindings too. If we want it in the bindings at all, that is. Ari thinks it's unnecessary.