feat: While converting to mantle map, also fill laneGroup with data.

This PR:

• Adds to the rls road class a new attribute: the id of the junction to which a road belongs a connection road
• According to OpenDRIVE this is a string. The value "-1" means no junction
• https://www.asam.net/index.php?eID=dumpFile&t=f&f=4422&token=e590561f3c39aa2260e5442e29e93f6693d1cccd#top-263d2bb0-9c50-4953-ae25-3ea2b94d0fdc
• While converting the internal data storage to mantle map, the new lane-group struct will be also filled with the needed information (id, type, lanes, lane_boundaries)