BBC Micro emulator for Windows, OS X, and Linux

Add first pass emulation support for the upcoming Retro Hardware Advanced Digital Joystick Interface cartridge
Fix double height teletext hold graphics state reset
Fix crash if attempting to OSRDCH paste an empty string
Fix various minor UI issues
Improve direct disk image speed, especially for writes
Improve multithreading generally (probably most noticeable as lower CPU usage when using lots of debugger displays)
Improve handling of non-ASCII chars in paths on Windows
Save current setting of Prioritize Command Keys
Tweak build setup very slightly to hopefully fix sporadic CI build issue
Tweak disk image options a bit: direct disk images are now just disk images, and disk images are now known as in-memory disk images. So if you pick what sounds like the default option, you won't lose changes when exiting
Update UI library - you'll have to recreate your window layout, sorry about this. I hope this won't happen again