Added the new bed models.

I'll wire them to the game once the new creature definition format will be in.
Atually linked the spider and tentacle beds to the corresponding creatures.

Fixes #229
Added the Orc Bed while on it.
Merge pull request #232 from hwoarangmy/development

Trap/Room creation in a more objet way (avoiding void* pointers)
Merge pull request #234 from Bertram25/new_models

New bed models
Simplified the way Chickens are handled in the hatchery
- Chickens can be picked up
- Chickens can be dropped on claimed tiles
- Chickens leave hatchery only when dropped outside
- Chickens can live 30 turns outside the hatchery. After that, they die
- Only creatures using the hatchery will consider eating a chicken in the hatchery
- A creature not using the hatchery will consider eating chickens outside the hatchery only. Any creature, even ennemy can eat a free chicken
fixes #216