laplace and agq estimation methods

nlmixr2 log-likelihood In 2022 we announced the focei log-likelihood. However, in our last advisory committee meeting Mats Karlsson pointed out that focei log-likelihood may not be the best approach. He believed that Stuart L. Beal and Lewis B. Sheiner did not include this method since they may have been trying to protect users from methods that may not make sense (for example, maybe focei log-likelihood is not an accurately enough approximation of the likelihood).