Merge branch 'master' into jgrpp

# Conflicts:
#	src/3rdparty/fmt/core.h
#	src/command_type.h
#	src/console_cmds.cpp
#	src/core/overflowsafe_type.hpp
#	src/landscape.cpp
#	src/network/network.cpp
#	src/newgrf_object.h
#	src/object_cmd.cpp
#	src/order_gui.cpp
#	src/saveload/vehicle_sl.cpp
#	src/script/api/script_industrytype.cpp
#	src/script/api/script_object.hpp
#	src/script/api/script_town.cpp
#	src/table/object_land.h
#	src/timetable_cmd.cpp
#	src/tree_cmd.cpp
#	src/vehicle_gui.cpp
#	src/window.cpp

src/timetable_cmd.cpp

@@ -36,6 +36,7 @@
 static void ChangeTimetable(Vehicle *v, VehicleOrderID order_number, uint32 val, ModifyTimetableFlags mtf, bool timetabled, bool ignore_lock = false)
 {
 	Order *order = v->GetOrder(order_number);
+	assert(order != nullptr);
 	int total_delta = 0;
 	int timetable_delta = 0;