What's New:
- fixes a potential crash on macOS when using File -> New... to create an empty machine.
- adds nascent Commodore 16/Plus 4 emulation, a work-in-progress;
- fixes a potential crash at startup for the MSX 2;
- reduces potential memory leaks for any machine that uses disks;
- improves the Mac UI with: a modern icon, improved menu wording and closer-to-QuickTime behaviour for showing the in-window machine controls; and
- experimentally, primarily for the ZX Spectrum and on macOS only, attempts automatically to relaunch media that has been changed by an external program (e.g. if you reassemble software you are developing).