A little work on creature distribution

Hmm, maybe I should start tagging with things like "tech", "graphics", "AI" ... but I'd probably just get lost in the tag cloud. Welp, I'll try it. This one is "structure", short for dungeon structure I suppose. I'd use architecture, but in software development that can mean quite a few things.

Way back when I had the idea of leveled critters, their level span would be quite large as they would grow with the player. Fortunately I threw that idea out, and so creatures will have a smaller level span - I'll just have more features. I think this will differentiate the levels a bit; more creature variety will show the player that their environment is changing. Goblins to goblin squads, wild dogs to wolves, kobolds to trolls and so on. At some point minibosses and such will start showing up, possibly leading squads - this *is* a defensive dungeon after all.

In any case, the code for this is now done and minimally tested (like most game features, ha!). It will take actual playtesting, further creature development, and probably a substantial amount of numbers tweaking to make it perfect, but "functioning" is good. I might add a few more creature variants today for starters.

Next up, that ranged combat. I'll have an *exciting* path-tracing screenshot later today.