added 2 new occbin.simul options (defaults preserve current behavior):

1) algo_truncation: sets the number of iterations for a truncated guess-verify algorithm (i.e. if max_iter<=algo_truncation, no error is triggered on output, but the user is happy with the last regime in the algorithm)
2) reset_regime_in_new_period: is set to true, it resets the guess regimes to unconstrained when a new shock arrives, instead of starting with a guess regime consistent with the one identified in previous time periods. this sometimes allows more robust convergence/identification of the regimes