Implement the conditional inclusion of literature-based defaults

Fully prevent the selection of a uniform distribution function when the
simulation will be stochastic and total mass action is selected (fix #130).

Resolve the issues related to the now-implemented UI and server functionality to
use literature-based model defaults. The list of literature-based defaults is
only added to the model selection dropdown when there is at least one
literature-based model; otherwise only the application-default compartmental
models are shown in the model selection dropdown (fix #11).

commented out standalone scripts

Update muB and muD globalValidator limits, update XLSX spreadsheet.

- The new limits for birth and death rates are taken from the global/planetary
data from https://www.ourworldindata.org. The birth rate limits are based on the
fertility rates described in https://ourworldindata.org/fertility-rate, and the
death rate is based on the entry "World" in the chart here:
https://ourworldindata.org/explorers/population-and-demography?facet=none&country=~OWID_WRL&Metric=Death+rate&Sex=Both+sexes&Age+group=Total&Projection+Scenario=None.

- The validation messages are a rough, quick and dirty attempt to describe the
limits to the user if they are violated and unreasonably large.