Factorize saving of smoother results used in dynare_estimation_1 and evaluate_smoother

In dynare_estimation_1 both the calibrated smoother and ML/MCMC without replications write the smoother results to oo_. The same holds true for evaluate_smoother.m. I would propose to outsource this code to a separate function that is easier to maintain (in particular when working on #679 (closed)). This would also make sure that the saving is consistent. Currently, I don't think the calibrated smoother saves all necessary fields.

If agreed upon, I would volunteer to do this.