* Removes the extensions to Opt4J such as creators, decoders, etc. that
  were based on the dependency management with JGraphT.
* Removes some more stubs from the architecture encoding.
* The JGraphT-based dependency graph is NOT yet removed, since the
  transformation framework has many dependencies upon it. It will be
  removed after migrating the transformation framework to Guide.

Issue-Ref: 3279
Issue-Url: https://af3-developer.fortiss.org/issues/3279


Signed-off-by: Alexander Diewald <diewald@fortiss.org>