TRS32 version 1.21

Added sound to the Stringy Floppy emulation (suggested by Terry Stewart, who also contributed the sound sample)
Improved the sound used by the floppy disk emulation
Fixed a problem with returning Stringy Floppy status (thanks to Terry Stewart)
Changed the floppy autostart order to favor the Model I (suggested by Ira Goldklang)
Fixed emulated floppy disk sector not found behavior (thanks to Ira Goldklang)
Added copy and paste features (suggested by Ira Goldklang)
Corrected behavior of an emulated Model I without lowercase