+ wait with timeout at loading screen
+ copy last frame of door animation to background
+ only dig if digger selected
+ ability to explode
+ particle effects
+ wait a second after last lemming gone to exit
+ update the "in" %
+ proper check for successful vs not end of level
+ ability to walk up hills
+ level 5
  -- door animation
  -- music
+ let's go sound
+ fill in some of the ground so we don't get stuck when digging
+ dig off the map, end level