IF Domain Model Feedback: Linking between DM and LRM + issue regarding object_distance method

Originated from https://code.asam.net/simulation/standard/openscenario-2.0/-/issues/324#note_30650

Some feedback from @Ali.Reza.Fayazi_Ridecell from the Ridecell Presentation from 2021-04-11:

• Is Domain Model version linked to OSC 2.0 language version?

  • OSC 2.0 language definition seems adequate; not sure if the Domain Model includes all elements needed for desired scenarios.

• It might come handy in scenario-execution if an optional parameter is added to object_distance() method to denote if the distance between the actor and the reference entity is “increasing”, “decreasing”, or “constant”.