Mbed OS based firmware compilation

Once Mbed OS project is set up, firmware can be compiled with simple command from terminal:

mbed compile --profile debug.json

and the resulting binaries can be found in ./BUILD/SENSORIO/GCC_ARM-DEBUG/ directory.

For optimized/release binary build command uses a different profile:

mbed compile --profile release.json

and the resulting binaries can be found in ./BUILD/SENSORIO/GCC_ARM/ directory.