Add "aggregation" function

[mstechly]

It would be useful to have a reliable way to add "aggregated costs" in bartiq.

I imagine the API would look sth like this:

aggregation_dict = {"effective_toffs": {"toffs": 1, "gidney_lelbows": 1}, "aggregated_t_gates": {"toffs": 4, "gidney_lelbows": 4, "t": 1, "rotation": 50}
alg_with_extra_resources = add_aggregated_resources(my_algorithm, aggregation_dict)