splineTo 
  Adds a spline segment with tangent heading interpolation.
Parameters
endPosition 
end position
endTangent 
end tangent
fun splineTo(endPosition: Vector2d, endTangent: Angle, velConstraintOverride: TrajectoryVelocityConstraint, accelConstraintOverride: TrajectoryAccelerationConstraint = builder.baseAccelConstraint): TrajectoryCommandBuilder
Adds a spline segment with tangent heading interpolation.
Parameters
endPosition 
end position
endTangent 
end tangent
constraintsOverride 
segment-specific constraints