Add "Phylum" attribute to mobs.

[ndouglas]

Story

As a developer, I want to define traits that are shared by groups of species so that I DRY.

I chose "phylum" not because this concept maps perfectly to the biological level of classification, but because it is unlikely to be used anywhere else.

This should allow biological traits to be determined by phylum, independently of faction -- which is a purely social construct.

Acceptance Criteria

• [ ] A concept of phyla is introduced into the codebase.
• [ ] A "goblinoid" phylum is introduced.
• [ ] Kobolds, orcs, ogres, goblins, etc are added to the "goblinoid" phylum.
• [ ] A "humanoid" phylum is introduced.
• [ ] Humans, elves, etc are added to the "humanoid" phylum.
• [ ] A "fungoid" phylum is introduced.
• [ ] Fungus men are added to the "fungoid" phylum.

Implementation Notes

[ndouglas]

The main reason it occurred to me to introduce this concept is to make e.g. all reptilian mobs have green blood, or something like that. However, it introduces issues with categorization (is a fungus zombie a fungoid or a human (or elf)?), etc, that are the whole reason that the ECS is being used.

So I think it's better for me to reimplement this using components rather than try to shove an inheritance system back in...