Add compile (grounding) options

[Core5563]

As far as i have seen there are two options for compiling/grounding:
remove_statics_from_initial_state, remove_irrelevant_operators
which are True by default.
I have a use case where the problem is unsolvable and actions, which i still need, are being removed.
If possible i would like a way to configure these two settings.

Note: I have already tried to simply set these two values (setting the value in the _ground function).
engine.py 121:

task = _ground(prob,remove_statics_from_initial_state=False, remove_irrelevant_operators=False)

Unfortunately this leads to an error in "rewrite_back_task":
grounder.py 60:

grounded_problem.set_initial_value(vars_to_fluent_map[init], True)

KeyError: '(x)'

The used Problem (unified_planning.shortcuts.Problem) is defined as follows:

    problem = Problem()
    #variables
    x = Fluent("x", BoolType())
    y = Fluent("y", BoolType())
    z = Fluent("z", BoolType())
    p = Fluent("p", BoolType())
    q = Fluent("q", BoolType())
    #add variables and set initial values
    problem.add_fluent(x, default_initial_value=True)
    problem.add_fluent(y, default_initial_value=False)
    problem.add_fluent(z, default_initial_value=False)
    problem.add_fluent(p, default_initial_value=False)
    problem.add_fluent(q, default_initial_value=False)
    #add goals
    problem.add_goal(p)
    problem.add_goal(q)
    #actions
    a1 = InstantaneousAction("a1")
    a1.add_precondition(x)
    a1.add_precondition(y)
    a1.add_effect(z, True)
    a1.add_effect(p, True)
    problem.add_action(a1)
    a2 = InstantaneousAction("a2")
    a2.add_precondition(z)
    a2.add_effect(q, True)
    problem.add_action(a2)