unique_value now works with multistates and only valid data
most_common_value added.
Cast dtypes to allow shorts for mapped arrays
Raname "Capt" to "Captain" and "FO" to "First Officer"
Pilot Flying supported in Takeoff and Landing pilot
Commented out code for control surface determination of PF re-enabled to ensure test cases pass and await information as to which aircraft types this does not apply to (e.g. 737 where both signals change together)
Headwind uses Airspeed before Windspeed to increase aligned frequency
Merge branch 'master' of github.com:FlightDataServices/FlightDataAnalyzer