Issues a rotate order to a ship to rotate to a given cell. The cell coordinates can be outside the map bounds.

#request rotation to face towards the center of the map
MapWidth 2 div ->x #half of the width in pixels
MapHeight 2 div ->y #half of the height in pixels
<-x <-y PixelToCell ->y ->x #convert pixels to cells
<-shipId <-x <-y RotateShipToCell