#TODO: help_string & usage_string:

gui/about.cpp
gui/browser.cpp
gui/chooser.cpp
gui/downloaddialog.cpp
gui/downloadiconsdialog.cpp
gui/editgamedialog.cpp
gui/editrecorddialog.cpp
gui/filebrowser-dialog.cpp
gui/fluidsynth-dialog.cpp
gui/gui-manager.cpp
gui/launcher.cpp
gui/massadd.cpp
gui/message.cpp
gui/onscreendialog.cpp
gui/options.cpp
gui/predictivedialog.cpp
gui/recorderdialog.cpp
gui/remotebrowser.cpp
gui/saveload-dialog.cpp
gui/themebrowser.cpp
gui/ThemeEngine.cpp
gui/unknown-game-dialog.cpp
gui/updates-dialog.cpp
gui/widget.cpp
gui/widgets/grid.cpp
gui/widgets/groupedlist.cpp

base/main.cpp

common/achievements.cpp
common/error.cpp
common/rendermode.cpp
common/updates.cpp
common/util.cpp

dists/scummvm.appdata.xml.cpp

engines/advancedDetector.cpp
engines/dialogs.cpp
engines/engine.cpp
engines/game.cpp
engines/metaengine.cpp
engines/savestate.cpp

graphics/renderer.cpp

audio/adlib.cpp
audio/fmopl.cpp
audio/mididrv.cpp
audio/mods/paula.cpp
audio/null.cpp
audio/null.h
audio/softsynth/appleiigs.cpp
audio/softsynth/cms.cpp
audio/softsynth/fluidsynth.cpp
audio/softsynth/fmtowns_pc98/towns_pc98_plugins.cpp
audio/softsynth/mt32.cpp
audio/softsynth/pcspk.cpp
audio/softsynth/sid.cpp

backends/cloud/cloudmanager.cpp
backends/cloud/storage.cpp
backends/dialogs/gtk/gtk-dialogs.cpp
backends/dialogs/macosx/macosx-dialogs.mm
backends/dialogs/win32/win32-dialogs.cpp
backends/events/default/default-events.cpp
backends/events/gph/gph-events.cpp
backends/events/maemosdl/maemosdl-events.cpp
backends/events/openpandora/op-events.cpp
backends/graphics/opengl/opengl-graphics.cpp
backends/graphics/openglsdl/openglsdl-graphics.cpp
backends/graphics/surfacesdl/surfacesdl-graphics.cpp
backends/graphics/sdl/sdl-graphics.cpp
backends/keymapper/hardware-input.cpp
backends/keymapper/remap-widget.cpp
backends/keymapper/virtual-mouse.cpp
backends/midi/windows.cpp
backends/networking/sdl_net/handlers/createdirectoryhandler.cpp
backends/networking/sdl_net/handlers/downloadfilehandler.cpp
backends/networking/sdl_net/handlers/filesajaxpagehandler.cpp
backends/networking/sdl_net/handlers/filespagehandler.cpp
backends/networking/sdl_net/handlers/indexpagehandler.cpp
backends/networking/sdl_net/handlers/listajaxhandler.cpp
backends/networking/sdl_net/handlers/uploadfilehandler.cpp
backends/networking/sdl_net/handlerutils.cpp
backends/networking/sdl_net/localwebserver.cpp
backends/networking/sdl_net/uploadfileclienthandler.cpp
backends/platform/3ds/options-dialog.cpp
backends/platform/3ds/osystem-events.cpp
backends/platform/android/options.cpp
backends/platform/ds/ds-graphics.cpp
backends/platform/ds/osystem_ds.cpp
backends/platform/ios7/ios7_osys_events.cpp
backends/platform/ios7/ios7_osys_main.cpp
backends/platform/iphone/osys_events.cpp
backends/platform/maemo/maemo.cpp
backends/platform/sdl/macosx/appmenu_osx.mm
backends/platform/sdl/ps3/ps3.cpp
backends/platform/sdl/psp2/psp2.cpp
backends/platform/sdl/switch/switch.cpp
backends/platform/wii/options.cpp
backends/presence/discord/discord.cpp
backends/updates/macosx/macosx-updates.mm