[Feature Request] Reorder windows inside stacks

[nermolov]

Expansion of #203 (comment)

Would be very helpful to organize windows more.

[Apolsus]

Support, It would be better if you could move the windows in piles, or remove one of them. It would be better if we could incorporate the functions of stackline.

[koekeishiya]

On master, yabai -m window --swap <window_sel> will now also work on windows that are in the same stack, instead of returning an error.

If both windows are in the same stack, the windows will swap place inside that stack.

If windows are in separate stacks, the entire stacks will swap places.

If one window is stand-alone (not a stack), and the other is a stack of windows, the lone wnidow will swap places with the entire stack.

[kiryph]

Do swap operations within a stack trigger any event? I want to redraw the stackline symbols to reflect the new order, similar to

AdamWagner/stackline#110