FIX:
    - Order.orderId ???
    - clean up Map4 from activated, activable stuff, maybe should stay in states !?!?
    - check unitId (static) after reinforcement arrive !!!
        - after JSON load Unit.unitId must be set to max()
    - load last turn synched
    - fix shoot animations, quit -> resume
    - Orders boolean:replay, [if needed : id->seq(hq activation->same seq)]
        - public Order map.prepareYxzOrder( )
        - postOrder()
        - ctrl set ANIMATION state + map.processOrder() -> save if not replay
        - at ANIMATION END, pay AP if needed (order.cost) ...

TODO:
    - turret aiming sound
    - moving cloudy sky overlay
    - Rules
        - 9.6 improved position as trait on Unit ??
        - 6.3 Russian mass activation
        - 8.6 Russian fire restrictions

NEXT:
    - support different board layout
        - north orientation
        - hex orientation
        - inverted even/odd row scheme
    - automatic overlays to show unit stack depth