GUI:
    Play ->
        Mode | Battle Name | Opponent | Status
        Mode | Battle Name | Opponent | Status
        Mode | Battle Name | Opponent | Status
        Mode | Battle Name | Opponent | Status

        New     |   Replay      | Continue



    New ->
        Mode : choice       Solo PvP PvE
        Battle: choice
        Description


    Replay -> Replay Ctrl
    Continue -> PvP | PvE reload ... play


TODO:
    - Replay Ctrl
    - 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