Enhancement: create an option to use either conditional distribution or conditional mode (EBEs) for random effect plots

[biencan1]

Currently all plots displaying random effects in ggPMX are based on conditional mode of EBEs which might be affected by shrinkage. To overcome this Monolix generates conditional distribution which is less affected by shrinkage and advised by Lixoft to be used random effect plots, in particular covariate vs random effect plots. At present ggPMX does not offer an option to use conditional distribution of random effects instead of EBEs in diagnostic plots. This would be a great enhancement if user could choose what option of random effect plots to use in the report.

[biethbr1]

@biencan1: thank you for the suggestion. It is related to the following ling from Monolix http://monolix.lixoft.com/faq/understanding-shrinkage-circumvent/

This would require changing the reader and add one option to EBE plots. TBD with @tynesjo