This includes:
- Using the class FullyImplicitBlackoilResidual instead of
in-class definition for the residual object.
- Changing residual field name mass_balance to material_balance_eq.
- Letting the simulator and solver classes accept a
FullyImplicitSystemSolverInterface instead of a LinearSolverInterface.
- In sim_fibo_ad and test_implicit_ad, instantiate class
FullyImplicitSystemSolverSimple, replicating existing behaviour.