Model upgraded into fully diameter-dependent model
The gravitational settling is now fully diameter dependent, as well as f_dep (fraction of virions deposited on the respiratory tract), using the formulas from the CARA paper (to be published). An evaporation factor (default value = 0.3) is also introduced in ConcentrationModel, reducing the size of the aerosols before applying the formulas.
Generally speaking, probability of infection is slightly decreased by the first, slightly increased by the second.
This completes the two remaining tasks of #184 (closed)