Minecraft wiki entry for Development_versions, associated text: Reordered spawn eggs in the creative inventory.
Changed spawn eggs colors to better represent their respective mobs they spawn.
Blaze
Cave Spider
Chicken
Cow
Creeper
Enderman
Ghast
Magma Cube
Mooshroom
Pig
Sheep
Silverfish
Skeleton
Slime
Spider
Squid
Villager
Wolf
Zombie
Zombie Pigman