updated minimum viable product

I think in order to release the first version of the game we should have the following:

- [x] leveling so the zombies get harder
- [x] zombies break walls
- [x] make the npc better
- [ ] a basic guide on how to play
- [x] better store
- [x] zombies attack crops
- [ ] better art for the player
- [ ] player skin selection (not really MVP but I wanna add it)
- [ ] melee too but if its too hard to code for now we can just take the knife out of player inventory