AP_InertialSensor: removed the flash_leds() callback

AP_Notify now handles this
libraries: fixed examples for no flash_leds() callback
Rover: removed flash_leds() calls
Copter: removed flash_leds() calls
Plane: removed flash_leds() calls
VARTest: removed old pin defines
Plane: disable battery failsafe when usb connected
gitignore: ignore Build.ArduPlane
AP_InertialSensor: fixed another example build
Plane: Auto Takeoff Check updates

Adds additional launch angle protection and protection against early
exit from auto causing unexpected motor start on re-entry
Plane: changed TKOFF_THR_DELAY default to 2

this makes it safer for hand launch with pusher props
Iris: enable battery failsafe by default
Plane: fixed AUTO_FBW_STEER stick mixing
Plane: fixed throttle suppression for AUTO_FBW_STEER=1
AP_Param: explicitly print floats to 6 dec places

C++ default is to print 6 decimal places but nuttx displays none by
default
DataFlash: explicitly print floats to 6 dec places

C++ default is to print 6 decimal places but nuttx displays none by
default
Iris: Change Flight Modes
Plane: fixed uartA baud rates for APM1
Rover: fixed baud rates on APM1
Copter: fixed baud rates on APM1