Generic/green robed (zombie) villagers aren't spawnable.

The green robe villager and zombie villager are no longer spawnable.
Note: the texture files still exist in the game files.

Perviously you could spawn them using:

/summon Villager ~ ~ ~ {Profession:5}
/summon Villager ~ ~ ~ {Profession:-1}
/summon Zombie ~ ~ ~ {IsVillager:1b,VillagerProfession:5}