put flight tasks in separate folder and create a lib for each
goal is to select tasks for targets (e.g. because of flash issue)

FlightTaskAuto: move generation of the the internal waypoints to FlightTaskAuto such that they are available to all derived classes.
Change logic to update the internal triplets only when the navigator triplets have changed or when the vehicle state has changed.

-add FlightTaskAutoMapper that handles the different types of waypoint and
generates setpoints for all types except of position and loiter
- FlightTaskAutoLine generates the setpoint types position and loiter if
the flight between waypoint is a straight line

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