* WinVideo: move some generic functions back to Video.
Introduce a new virtual function (VideoPresentScreen) to draw the video buffer to video memory.
* Move Win32Frame::VideoRedrawScreen() to FrameBase as it is generic.
. class hierarchy: WinVideo IS_A Video (ie. WinVideo is a subclass of Video)
. GetVideo() singleton instance of WinVideo in AppleWin.cpp, exposed via Interface.h
* Interface.h: ensure that functions in the interface are not exported by other header files.
This is generally harmless, except for the presence of default arguments, in which case the version with default arguments must come first.
To avoid the issue, these functions are only ever exported in the Interface.h header file.
. Split AppleWin -> Core with the functionality really needed by the emulator.
. Split AppleWin -> Utilities for generic code not called by other emulator components.
. Split AppleWin -> CmdLine for the command line option parsing.
