changelog

- added new special: motivate
- added another evolve level for mushroom and cacti
- added a big unit: melon
- flowers changed a lot!
they don't regularly spawn units anymore;
they now help evolve units, heal them and spawn big units (pumpkins/melons) when they have all their petals
- made specials a lot stronger
- fixed flowers not spawning pumpkins when full
- misc. balancing changes
- misc. bug fixes