Key blinker support for LEDs mode, matrix sanity diagnostics

"solenoid" blinks the ExpHdr2 in all modes now. This means ScrLock LED had to move, and xwhatsit expansion header compatibility is lost. And this is fine - if I ever make a custom hardware, it will have incompatible expansion header which will not fry any of the components if plugged in reverse (or have a key ensuring correct orientation).
Since this is a major change - firmware is bumped to 1.1 and software to 1.0.1.0

When sanity check trips - matrix monitor and threshold editor will display the noisy cells in red after couple of seconds.

Fixed handling of empty layout cells - they no longer produce random scancodes.

Built with qt 5.14.1