Firmware update

There is too many changes to list all of them correctly the most important are:

• Fixed power off button
• Fixed wrong pin mapping for LCD power
• Add instructions for PCA9555D
• Added instructions on how to callibrate temperature sensor
• Fixed battery voltage measurement
• Rewrote code for thumbstick not to use sleep
• Added many more mutantctl knobs

• more

Signed-off-by: Cyril Hrubis metan@ucw.cz