WaveCatcher: 200MSps portable oscilloscope

Just added USB support.
I'm using TinyUSB and FatFS, on FreeRTOS.
The scope can now save screenshots of the screen in BMP format!

Also, I wrote a buildloader and separated the project in two executables: the buildloader, and the main application.
The bootloader runs with minimal-simplified graphics, no RTOS and fit in 32KB first flash sector.
Now user can update the firmware of the STM32 with USB key!