The resource manager now keeps track of its cif trees and calls to loadImage() and loadData() don't need to specify a cif tree. In order to support The Vampire Diaries, IFFs can now be loaded from their own dedicated .iff file, and the engine doesn't require a cif tree to be loaded on boot.
Made all states (Scene, Credits, Help, etc.) singletons, as well as subclasses of a common State parent with a proper state switching API. Moved the OnPause virtual function from RenderObject to ActionRecord and hooked it into the state switching code. Also got rid of the NancyEngine pointer that got passed around between most classes, and replaced it with several convenience macros. As a result of these changes action records that render to the viewport no longer disappear after opening the menu, and state changes feel snappier.
Added initial support for savestates. The format will most likely change with future commits, but I will only start versioning once the engine supports more than a single game. To support proper serialization the Scene state has had its kInit state split into kInit and kInitStatic, InventoryBox had some of its code reordered, and members of several classes have had their types changed.
Renamed all functions relating to the engine's internal state so they only mention the word State instead of GameState. This is to avoid confusion between them and functions relating to savegames, whose names already include GameState.
The original engine stores sound information in at least four different types of structs, all of which can now be loaded and played back. Also implemented sound types, which will be configurable from the ScummVM interface, added the correct number of sound channels, and implemented sound fx in a couple of action record types.
Rewrote most of the engine using a much more object-oriented approach and using more of ScummVM's common classes. This design deviates quite a lot from the original engine's, but should be more maintainable and extensible in the future.
