TONY: Switch to 565 screen format.

The old (555) screen format is not supported by some backends.

This leaves the savegame thumbnails as 555 (for compatibility).
COMMON: Use true nullptr in Visual Studio 2010+ and true override in VS 2012+

Those compilers support these features despite not being fully C++11-compliant.

<http://msdn.microsoft.com/en-us/library/hh567368.aspx> says that VS 2010
has "partial" support for override. I don't know what that entails and I
can't test it, so I err on the side of caution and only enable it in 2012
and up.
CGE: Add a safeguard in getPage()
DRASCULA: Remove unused static variable

This code was used until commit aaf8b58 that reworked the detection
to support French and German versions.
KYRA: (EOB) - add support for Italian fan translation of EOB I
AMIGAOS4: Fix getParent() for non-directories

The previous attempt in d32816c0 was broken because it failed
to realize that _pFileLock is only set for directories.

This patch also tries to clarify this by making the root node logic
explicit in isRootNode().
MADS: Fix loading wide-screen backgrounds during intro animation
MADS: Fix palette animations in cutscene animations
TSAGE: R2R - Add comments in scene 1337, some renaming
TSAGE: R2R - More renaming in scene 1337, add some comments
TSAGE: R2R - Remove a hack in playCentralOutpostCard()
TSAGE: R2R - Fix a bug in scene 1337, when playing a meteor card on a player owning an interceptor card
MADS: Fix horizontal background scrolling in animations
MADS: Depth style 2 frames can be drawn using existing methods
TSAGE: R2R - Fix discard of own selected station when handling the meteor card effect
TSAGE: R2R - Fix bug with short delay card discard for player 0
MADS: Better initialization of animation cycling palettes
MADS: Move OPL creation from the engine to SoundManager
TSAGE: R2R - Remove a hack in Scene1337::Action12
TSAGE: R2R - Some more renaming in scene 1337