remove combined {models,sprites}.mat, remove extra .mdl .spr exts

bshift/pbr/models/barney_helmet.mdl/barney_helmet.mat

@@ -0,0 +1,24 @@
+
+{
+"for" "#models/barney_helmet/bottom_helmet.mdl"
+//"basecolor_map" "bottom_helmet.png"
+//"normal_map" "bottom_helmet_normal.png"
+//"metal_map" "bottom_helmet_metal.png"
+//"roughness_map" "bottom_helmet_roughness.png"
+}
+
+{
+"for" "#models/barney_helmet/chrome_helmet.mdl"
+//"basecolor_map" "chrome_helmet.png"
+//"normal_map" "chrome_helmet_normal.png"
+//"metal_map" "chrome_helmet_metal.png"
+//"roughness_map" "chrome_helmet_roughness.png"
+}
+
+{
+"for" "#models/barney_helmet/side_helmet.mdl"
+//"basecolor_map" "side_helmet.png"
+//"normal_map" "side_helmet_normal.png"
+//"metal_map" "side_helmet_metal.png"
+//"roughness_map" "side_helmet_roughness.png"
+}