Add help button in main menu (opens Hedgewars Wiki in browser)
Might be replaced with an offline help in later versions (see
bug #660).
foreach(dir
Fonts
Forts
Graphics
Locale
Maps
Missions
Music
Names
Scripts
Sounds
Themes
misc
)
add_subdirectory(${dir})
endforeach(dir)
if(${GL2})
add_subdirectory(Shaders)
endif(${GL2})