The DOS version of Simon 1 has different music tempos compared to the Windows
version. This commit adds the option to both the DOS and Windows MIDI parsers
to use either the DOS or Windows tempos.
This commit adds MIDI parser subclasses for the Simon 1 GMF format and for the
SMF variant used by the Windows versions of Simon 1 and 2.
The GMF format was handled by the SMF parser, which can now be removed from
that class. It also fixes the tempos not matching the DOS interpreter.
The Simon Windows SMF variant was handled in the AGOS midi class. Moving it to
a separate parser allows for some cleaner code in that class. It now also
corrects the tempos to match those of the DOS interpreter.
