Add company setting to auto-enable auto timetables for new vehicles.

Default: off.

src/settings_gui.cpp

@@ -1586,6 +1586,7 @@ static SettingsContainer &GetSettingsTree()
 			company->Add(new SettingEntry("vehicle.servint_roadveh"));
 			company->Add(new SettingEntry("vehicle.servint_ships"));
 			company->Add(new SettingEntry("vehicle.servint_aircraft"));
+			company->Add(new SettingEntry("vehicle.auto_timetable_by_default"));
 		}
 
 		SettingsPage *accounting = main->Add(new SettingsPage(STR_CONFIG_SETTING_ACCOUNTING));