Fixes #1785
Companion bug in model import fixed (after changing radio in the same
session)
Sky9x binary was built with the bootloader present on disk (was not
removed by make clean). So 99% it was a Taranis bootloader.
Sky9x Coprocessor bug fix
It was possible to have the Limits contextual menu displayed in
READ_ONLY mode
Re #1610:
* sport.log only active if SPORT_FILE_LOG=YES
* audio concurrent access fixes
* added IO mutex
* added Event Trace Buffer
* fixed SD card error

Conflicts:
	radio/src/Makefile
	radio/src/targets/taranis/diskio.cpp
Cosmetics
Fixes for simu
Shutdown sound - bye.wav - A little bit related to #719
Bug in numbering of Lua multiple fields (only in generated documentation file, all numbers were too small by 1)
Telemetry refactoring start ... Only S.PORT for now. Sensors discovered
automatically. Still a lot missing.
Fix default precisions
Delete telemetry sensor wasn't stored
Telemetry refactoring continued
Cells sensor is now working (only Cels/Cels-/Cels+)
Now we can display voltage of each cell, or lowest/highest (from any
Cells sensor)
Add and Average formulas now working. It's possible to have many Cells
sensor either in parallel, or in serial.
Compilation fixes on !ARM boards + Companion
GPS fields added
Now the user will choose his preferred unit and precision (the same used
for display/voice/logs)