* what to do when stuck under tiles (after using duck-sliding)
* do we want multi hit scores again?
* tux doesn't stop at igloo anymore
+ * background particle systems are too slow
--Code Refactoring/Cleanup/Optimisation--
[H] make the title using GameSession instead of reimplementing all the stuff
- New forest tileset
- Badguy sprites
- Tux's buttjump animation
-[H] Background code have the following bugs:
- - Gradient in software rendering doesn't currently work (at least here).
- Matze: can you give more details? The code looks perfectly fine to me
[M] Save score on per-level basis to make high-score
[M] Save time on per-level basis to make low-time-score