* Wire.begin removed from AP_Baro_BMP085::init()
* SPI.begin removed from AP_Baro_MS5611::init()
* SPI.begin removed from AP_InertialSensor_MPU6000::hardware_init()
* Both Wire.begin and SPI.begin added very early in init_ardupilot in
ArduCopter/system.pde and ArduPlane/system.pde
this abstracts the way of getting inertial sensor (gyro and
accelerometer) data for the APM1 and purple hardware. The Oilpan code
is based closely on the old APM1 code