#TODO: help_string & usage_string:

gui/about.cpp
gui/browser.cpp
gui/chooser.cpp
gui/error.cpp
gui/gui-manager.cpp
gui/KeysDialog.h
gui/KeysDialog.cpp
gui/launcher.cpp
gui/massadd.cpp
gui/options.cpp
gui/saveload-dialog.cpp
gui/themebrowser.cpp
gui/ThemeEngine.cpp
gui/widget.cpp

base/main.cpp

common/error.cpp
common/util.cpp

engines/advancedDetector.cpp
engines/dialogs.cpp
engines/engine.cpp
engines/agi/detection.cpp
engines/agi/saveload.cpp
engines/dreamweb/detection.cpp
engines/sci/detection.cpp
engines/scumm/dialogs.cpp
engines/scumm/help.cpp
engines/scumm/scumm.cpp
engines/mohawk/dialogs.cpp
engines/mohawk/myst.cpp
engines/mohawk/riven.cpp
engines/cruise/menu.cpp
engines/sci/engine/kfile.cpp
engines/agos/saveload.cpp
engines/agos/animation.cpp
engines/gob/inter_playtoons.cpp
engines/gob/inter_v2.cpp
engines/gob/inter_v5.cpp
engines/groovie/detection.cpp
engines/groovie/script.cpp
engines/kyra/detection.cpp
engines/kyra/lol.cpp
engines/kyra/sound_midi.cpp
engines/queen/queen.cpp
engines/sky/compact.cpp
engines/sky/detection.cpp
engines/sword1/animation.cpp
engines/sword1/control.cpp
engines/sword1/logic.cpp
engines/sword1/sword1.cpp
engines/sword2/animation.cpp
engines/sword2/sword2.cpp
engines/teenagent/resources.cpp
engines/tinsel/saveload.cpp
engines/toltecs/detection.cpp
engines/toltecs/menu.cpp
engines/parallaction/saveload.cpp

audio/fmopl.cpp
audio/mididrv.cpp
audio/musicplugin.cpp
audio/null.h
audio/null.cpp
audio/mods/paula.cpp
audio/softsynth/adlib.cpp
audio/softsynth/appleiigs.cpp
audio/softsynth/sid.cpp
audio/softsynth/mt32.cpp
audio/softsynth/pcspk.cpp

backends/keymapper/remap-dialog.cpp
backends/midi/windows.cpp
backends/platform/ds/arm9/source/dsoptions.cpp
backends/platform/iphone/osys_events.cpp
backends/platform/maemo/maemo.cpp
backends/platform/sdl/macosx/appmenu_osx.mm
backends/graphics/surfacesdl/surfacesdl-graphics.cpp
backends/graphics/opengl/opengl-graphics.cpp
backends/graphics/openglsdl/openglsdl-graphics.cpp
backends/platform/symbian/src/SymbianActions.cpp
backends/platform/symbian/src/SymbianOS.cpp
backends/events/symbiansdl/symbiansdl-events.cpp
backends/platform/wii/options.cpp
backends/platform/wince/CEActionsPocket.cpp
backends/platform/wince/CEActionsSmartphone.cpp
backends/platform/wince/CELauncherDialog.cpp
backends/platform/wince/wince-sdl.cpp
backends/events/default/default-events.cpp
backends/events/gph/gph-events.cpp
backends/events/openpandora/op-events.cpp
backends/updates/macosx/macosx-updates.mm
backends/platform/bada/form.cpp
backends/events/maemosdl/maemosdl-events.cpp