eggs and spawners

changed ore generation to be between y levels 1 and 12

added the passive mobs:

pig (requires grass around spawner)

chicken (requires grass around spawner)

cow (requires grass around spawner)

sheep (requires grass around spawner)

rabbit (requires grass around spawner)

mooshroom (requires mycelium around spawner)

cod (requires water around spawner)

salmon (requires water around spawner)

squid (requires water around spawner)

bee (requires grass around spawner)

turtle (requires sand around spawner)

wolf (requires grass around spawner)

cat (requires grass around spawner)

llama (requires grass around spawner)

donkey (requires grass around spawner)

mule (requires grass around spawner)

horse (requires grass around spawner)

parrot (requires grass around spawner)