Add generic callback configuration logic

[PGijsbers]

You can configure callbacks for AutoGluon through configuration, e.g.:

AutoGluonES:
  extends: AutoGluon
  params:
    callbacks:
      EarlyStoppingEnsembleCallback:
        patience: 5

Should probably also be added to the time series script (might be worth at some point trying to see what can be stored in a shared module?)?

[PGijsbers]

@israel-cj I believe this should allow you to specify the callbacks in the way you need to for your experiments, while providing a more general approach for all users.