. 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.
Changes to ease code compilation in GCC.
Disk_t and HDD contain a std::string and for this reason they need a proper constructor, ZeroMemory is not guaranteed to work.
Also:
. support new CpuType independently of Apple2Type
. save-state: don't save disk track image if no disk
. save-state: re-init AppleWin internals & UI to reflect changed Apple2Type