Update mobs mod

- add chicken/chicken_black models
- add DM_strangewhite/DM_cobblestone models
- add rat/rat_brown models
- add the support for multiple textures/models in
rat.lua/sandmonster.lua/spider.lua/stonemonster.lua/treemonster.lua
- add the honey_block texture

mods/mobs/spider.lua

@@ -6,7 +6,11 @@ mobs:register_mob("mobs:spider", {
 	hp_min = 30,
 	hp_max = 35,
 	collisionbox = {-0.9, -0.01, -0.7, 0.7, 0.6, 0.7},
-	textures = {"mobs_spider.png"},
+	--textures = {"mobs_spider.png"},
+	available_textures = {
+		total = 1,
+		texture_1 = {"mobs_spider.png"},
+	},
 	visual_size = {x=7,y=7},
 	visual = "mesh",
 	mesh = "mobs_spider.x",