Rover: fixed comments
Rover: added 'level' CLI and reboot command
Rover: tweaked parameters and added SPEED_TURN_GAIN and SPEED_TURN_DIST
Plane: update SERIAL0_BAUD parameter description
HAL_AVR: expand analog input test to more channels
HAL_AVR: fixed analog input with high channel numbers
AP_HAL: moved AnalogIn example to generic examples

it is not AVR specific anymore