Implemented Second Chance, which is the original engine's autosave system. This is disabled by default, since it replaces ScummVM's built-in autosaves.
Moved CheatDialog and EventFlagDialog to dialogs.h and removed cheat.h. Fixed a crash on closing the event flags dialog. Fixed the timer data in CheatDialog being incorrectly written to the player time. Removed a couple of incorrectly marked translation strings.
Implemented the original engine's main menu and added an option to enable it from the custom options dialog. Several buttons in the main menu don't work yet since they require implementing additional game states.
Hooked the engine into ScummVM's speech/subtitle settings, and added two extra options for player and character speech. Added a custom settings dialog which gets shown both inside the Edit Game window and the in-game Settings.
