Nearing completion, but what do you think?

These are the new things added
- Achievements
- Titlescreen song
- More sound effects
- Graphical information that helps solving level 2
- Per animal a different visual effects for animals leaving the screen
- In survival mode: a timer to track how long you can stay alive.

I changed some backgrounds.

And I fixed some sound, gameplay and score display issues.

What do you think of this version?