autotest: use mavflightview.py from $PATH
Copter: run GPS glitch detection even when not armed
AP_HAL: support uartD on some boards

PX4 and SITL get an extra UART
HAL_AVR: added NULL uartD
HAL_SITL: added uartD
HAL_EMPTY: added uartD
HAL_FLYMAPLE: added uartD
HAL_LINUX: added uartD
HAL_PX4: added uartD
GCS_MAVLink: added support for 3 UARTs

support 3 UARTs on non-AVR platforms
Plane: added 3rd telemetry stream on platforms that have it

this generalises the gcs object usage
PX4: setup uartD on PX4

on FMUv1 enable uartD only if /fs/microsd/APM/uartD.en exists

on FMU2 always enable uartD
AP_Baro: fixed BMP085 examples build in autotest
HAL_FLYMAPLE: removed incorrect Makefile target
AP_Motors: removed incorrect Makefile target
Plane: fixed mavlink_queue[] size
Plane: rename geofence structure

makes using gdb easier as it doesn't mix up the structure and the
pointer
HAL_EMPTY: prevent valgrind errors

zero I2C transfers
Plane: send SIMSTATE messages in HIL

this allows better tracking of the simulator state, to see if issues
are caused by DCM failure
Plane: reset HIL attitude if off by more than 5 degrees