Additional changes:
- PVD voltage detector added
- Mutex for multitask I2C access added
- Semaphore for RF data ready signaling added
- Timer for releasing collision event added
- Timer for releasing radio events added
- Semaphore for synchronization of I2C devices added
- Accelerometer and gyroscope procedures moved to mod_sensors.c
- Text scrolling in mod_lcd.c for various events prepared to be changes