achievements and performance

Dear players,

Lots of stuff have been added this week:

• last cutscene of the game
• achievement screen and several achievements
• improvement of performance, mostly lessened the load of some bottlenecks (if you still have issues 1- try to toggle off v-sync 2- tell me where)
• minor changes

If you notice any odd behaviour, please let met know !

Progress will be slower next weak, I will take time to slow things down a bit and bring small touches, and next week-end will be dedicated to participating to ludum dare.

Have fun :)