phase out brown and white plastic images

use a colorized dark "black" one as the base.

homedecor/clocks.lua

@@ -4,7 +4,7 @@ local clock_sbox = {
 }
 
 local clock_materials = {
-	{ "plastic", "homedecor_generic_plastic_white.png" },
+	{ "plastic", "homedecor_generic_plastic_black.png^[colorize:#ffffff:220" },
 	{ "wood", "default_wood.png" }
 }
 

homedecor/lighting.lua

@@ -501,7 +501,7 @@ homedecor.register("ceiling_lamp", {
 		"homedecor_generic_metal_brass.png",
 		"homedecor_ceiling_lamp_glass.png",
 		"homedecor_table_standing_lamp_lightbulb.png^[colorize:#ffffff:200",
-		"homedecor_generic_plastic_brown.png",
+		"homedecor_generic_plastic_black.png^[colorize:#442d04:200",
 	},
 	inventory_image = "homedecor_ceiling_lamp_inv.png",
 	light_source = LIGHT_MAX,
@@ -519,7 +519,7 @@ homedecor.register("ceiling_lamp_off", {
 		"homedecor_generic_metal_brass.png",
 		"homedecor_ceiling_lamp_glass.png",
 		"homedecor_table_standing_lamp_lightbulb.png",
-		"homedecor_generic_plastic_brown.png",
+		"homedecor_generic_plastic_black.png^[colorize:#442d04:200",
 	},
 	groups = {snappy=3, not_in_creative_inventory=1},
 	walkable = false,