If there is a certain type of Zombie you want me to add, let me know, I'll see what I can do. Also I've created a super easy to use base texture in .kra, .psd, and .xcf format, if you want to add a texture feel free to create a pull request or upload the file and send me a link and I'll add it.
Screenshots.
Github:
https://github.com/minetest-mods/zombies
Download
https://github.com/minetest-mods/zombies/archive/master.zip
Depends on, Default, Cityscapes?, and Mobsredo.
License: CC by SA for graphics. Code is copied and pasted from the mobs api which is under MIT license.