Merge branch 'master' into jgrpp

# Conflicts:
#	src/company_cmd.cpp
#	src/core/geometry_func.cpp
#	src/date.cpp
#	src/genworld_gui.cpp
#	src/gfx.cpp
#	src/object_gui.cpp
#	src/openttd.cpp
#	src/settings_type.h
#	src/video/allegro_v.cpp
#	src/video/dedicated_v.cpp
#	src/video/null_v.cpp
#	src/video/sdl2_v.cpp
#	src/video/sdl_v.cpp
#	src/video/win32_v.cpp

src/gfx_func.h

@@ -80,6 +80,7 @@ void UpdateWindows();
 void DrawMouseCursor();
 void ScreenSizeChanged();
 void GameSizeChanged();
+void UpdateGUIZoom();
 void UndrawMouseCursor();
 
 /** Size of the buffer used for drawing strings. */