Add hit_points as a new message

[ClemensLinnhoff]

Describe the feature

Add individual hit points of a ray tracer as a new message to the SensorView.

Describe the solution you would like

Add a repeated HitPoint hit_point to the SensorView message with the following definition:

• HitPoint
  • Vector3D position
  • float incidence_angle
  • Identifier object_id
  • Identifier ray_id
  • String open_material_reference
  • repeated HitPoint child_hit_point

Every hit point has a position in world coordinates, the angle of incidence on the surface with respect to the face normal, the id of the object it hit and the id of the initial ray.
It also has a reference to an ASAM OpenMATERIAL file, to refer to the material of the surface.
Lastly, it has a repeated field for subsequent hit points that are hit by reflection or transmission during the further ray propagation through the scene.

Describe alternatives you have considered

An alternative is described in #825. This new approach would overcome the limitations and backwards compatibility problems described in #825.

Describe the backwards compatibility

New message, so there are no backwards compatibility issues.