This is intended to allow resizing of the game window. To minimize the work involved, we leave all dimensions in the source for a 800x500 window, and then call the adjwidth/adjheight/adjpos/adjrect functions to get the correct dimensions. In driver.py, resize image assets to the appropriate size. Also, create new resource 'rsprites' to contain the reversed version of the sprites, instead of flipping them every frame. In all other functions, use the resize functions appropriately. Change the duck icon width to 18 to match the source.