FlightTaskAuto: abstract class for mapping triplets to quadruple

FlightTaskAuto: add type that corresponds to triplet type

FligthTaskAuto: set all setpoints if invalid in xy

FlightTaskAuto: cast triplet type to WaypointType

FlightTaskAutoLine: class for px4 legacy auto

FlightTaskAutoLine: methods prototype

FlightTaskAuto: change sp to wp (=Waypoint)
add params

FlightTaskAutoLine: follow waypoints along line based on flight state