Post-process ADIS flight data using calibration log

[jameysharp]

We did a somewhat ad-hoc calibration procedure before this flight, so we have a log of ADIS data with the airframe pointing in a bunch of directions (2.6GB). That should let us calibrate out hard and soft iron effects in the magnetometer as well as accelerometer and gyro biases. We need to compute those bias parameters and then correct the flight data using them.