Gk browser drag reorder array

Possible to drag array items to reorder. Animated.

Requires change in bindings

https://app.asana.com/0/15028213105325/13316669162245
Remove this `if` statement altogether. I see what you're trying to do, but it shouldn't work like that. The index that's passed in should be respected.

If I have an RLMArray of two objects, and I say `moveObjectFromIndex:0 toIndex:1`, it should swap the order of both objects.