More Zombie Variants!

Adds 2 new zombie variants!

The first zombie variant is a zombie with a red shirt called a “Commander Zombie” they spawn in by themselves with 40 health, double the amount of a regular player, with a diamond helmet, diamond boots, and a diamond sword. They are a force to be reckoned with and when they die 3 trained zombies will spawn in it’s place.

The second zombie variant is called a “Trained Zombie” they have 20 health, full diamond armor, and an iron sword. Despite having more armor than a commander zombie they are far easier to kill.