Merge branch 'master' into jgrpp

# Conflicts:
#	src/ai/ai_core.cpp
#	src/ai/ai_gui.cpp
#	src/ai/ai_instance.cpp
#	src/console_cmds.cpp
#	src/engine_type.h
#	src/game/game_gui.cpp
#	src/game/game_instance.cpp
#	src/goal.cpp
#	src/goal_cmd.h
#	src/lang/english.txt
#	src/lang/estonian.txt
#	src/network/network_client.cpp
#	src/newgrf.cpp
#	src/newgrf_generic.h
#	src/openttd.cpp
#	src/saveload/saveload.h
#	src/script/api/script_log.cpp
#	src/script/api/script_town.cpp
#	src/settings_table.cpp
#	src/station_cmd.cpp
#	src/station_cmd.h
#	src/station_map.h
#	src/strings.cpp
#	src/table/settings/difficulty_settings.ini
#	src/table/settings/gui_settings.ini
#	src/tbtr_template_gui_main.h
#	src/timetable_cmd.cpp
#	src/timetable_cmd.h
#	src/timetable_gui.cpp
#	src/town_gui.cpp
#	src/train_gui.cpp
#	src/water_cmd.cpp

src/newgrf_airporttiles.cpp

@@ -23,6 +23,7 @@
 
 #include "safeguards.h"
 
+extern uint32 GetRelativePosition(TileIndex tile, TileIndex ind_tile);
 
 AirportTileSpec AirportTileSpec::tiles[NUM_AIRPORTTILES];
 
@@ -164,8 +165,6 @@ static uint32 GetAirportTileIDAtOffset(TileIndex tile, const Station *st, uint32
 {
 	assert(this->st != nullptr);
 
-	extern uint32 GetRelativePosition(TileIndex tile, TileIndex ind_tile);
-
 	switch (variable) {
 		/* Terrain type */
 		case 0x41: return GetTerrainType(this->tile);