SSoverlays for human icons, mostly works

Closer to working 100%

But legitimately /tg/ icons

Move lighting to it's own plane, fix observers

Fix humans layering over other objects incorrectly

Nyaaaaa~

code/modules/mob/dead/observer/observer.dm

@@ -48,8 +48,7 @@ var/list/image/ghost_darkness_images = list() //this is a list of images for thi
 
 		if(ishuman(body))
 			var/mob/living/carbon/human/H = body
-			icon = H.stand_icon
-			overlays = H.overlays_standing
+			appearance = H.appearance
 		else
 			icon = body.icon
 			icon_state = body.icon_state