Merge branch 'master' into jgrpp

# Conflicts:
#	src/airport_gui.cpp
#	src/build_vehicle_gui.cpp
#	src/direction_type.h
#	src/gfx_type.h
#	src/group_gui.cpp
#	src/misc_gui.cpp
#	src/rail_gui.cpp
#	src/road_gui.cpp
#	src/signs_gui.cpp
#	src/slope_func.h
#	src/smallmap_gui.cpp
#	src/terraform_gui.cpp
#	src/toolbar_gui.cpp
#	src/town_gui.cpp
#	src/town_type.h
#	src/vehicle_type.h
#	src/widget_type.h

src/waypoint_gui.cpp

@@ -217,7 +217,7 @@ public:
 };
 
 /** The widgets of the waypoint view. */
-static const NWidgetPart _nested_waypoint_view_widgets[] = {
+static constexpr NWidgetPart _nested_waypoint_view_widgets[] = {
 	NWidget(NWID_HORIZONTAL),
 		NWidget(WWT_CLOSEBOX, COLOUR_GREY),
 		NWidget(WWT_PUSHIMGBTN, COLOUR_GREY, WID_W_RENAME), SetMinimalSize(12, 14), SetDataTip(SPR_RENAME, STR_BUOY_VIEW_CHANGE_BUOY_NAME),