Merge branch 'master' into jgrpp-beta

# Conflicts:
#	src/saveload/cargopacket_sl.cpp
#	src/saveload/cheat_sl.cpp
#	src/saveload/company_sl.cpp
#	src/saveload/engine_sl.cpp
#	src/saveload/map_sl.cpp
#	src/saveload/order_sl.cpp
#	src/saveload/saveload.cpp
#	src/saveload/saveload.h
#	src/saveload/station_sl.cpp
#	src/saveload/vehicle_sl.cpp
#	src/settings.cpp
#	src/settings_gui.cpp
#	src/settings_internal.h
#	src/stdafx.h
#	src/table/settings/settings.ini
#	src/town_cmd.cpp
#	src/vehicle.cpp

src/gfxinit.cpp

@@ -106,8 +106,7 @@ static void LoadGrfFileIndexed(const char *filename, const SpriteID *index_tbl,
 		uint end = *index_tbl++;
 
 		do {
-			bool b = LoadNextSprite(start, file, sprite_id);
-			(void)b; // Unused without asserts
+			[[maybe_unused]] bool b = LoadNextSprite(start, file, sprite_id);
 			assert(b);
 			sprite_id++;
 		} while (++start <= end);