BestDose requests

[mhovd]

@R-garreau asked for the following:

• Separate functions from Pmetrics, so that Pmetrics doesn't have to be loaded in full
• Access to posterior parameter values and probabilities for past data
• Option to disable logs for BestDose
• Access to "raw" predictions and their probabilities (both posterior and population?)

@R-garreau, if you can provide a "wishlist" for the API and how you prefer to work with data and results then we can do larger iterations.

• The ecosystem to read and parse file to to run BestDose is available here LAPKB/BestDoseApp/issues/15
• The way data is handle by the software is available 🔜