Add setting to scale primary industry cargo production

src/industry_gui.cpp

@@ -1104,7 +1104,7 @@ static void UpdateIndustryProduction(Industry *i)
 
 	for (byte j = 0; j < lengthof(i->produced_cargo); j++) {
 		if (i->produced_cargo[j] != CT_INVALID) {
-			i->last_month_production[j] = 8 * i->production_rate[j];
+			i->last_month_production[j] = ScaleQuantity(8 * i->production_rate[j], _settings_game.economy.industry_cargo_scale_factor);
 		}
 	}
 }