add blank material files

bshift/pbr/models/gasbag.mdl/gasbag.mdl.mat

@@ -0,0 +1,8 @@
+
+{
+"for" "#models/gasbag/xeno_6aw1c.mdl"
+//"basecolor_map" "xeno_6aw1c.png"
+//"normal_map" "xeno_6aw1c_normal.png"
+//"metal_map" "xeno_6aw1c_metal.png"
+//"roughness_map" "xeno_6aw1c_roughness.png"
+}