WS function done, some documentation, and reorganization

CovidAlertVaccinationModel/src/CovidAlertVaccinationModel.jl

CovidAlertVaccinationModel/src/data.jl

CovidAlertVaccinationModel/src/mixing_distributions.jl

IntervalsModel/plots/Distributions.Poisson_hh.pdf

IntervalsModel/plots/Distributions.Poisson_rest.pdf

IntervalsModel/plots/Distributions.Poisson_ws.pdf

IntervalsModel/plots/hh.pdf

IntervalsModel/plots/rest.pdf

IntervalsModel/plots/ws.pdf

IntervalsModel/simulation_data/hh.dat

IntervalsModel/simulation_data/rest.dat

IntervalsModel/simulation_data/ws.dat

IntervalsModel/src/IntervalsModel.jl

IntervalsModel/src/hh_durations_model.jl

IntervalsModel/src/plotting_functions.jl

IntervalsModel/src/rest_durations_model.jl

IntervalsModel/src/utils.jl

IntervalsModel/src/ws_durations_model.jl

IntervalsModel/src/ws_rest_durations_model.jl

ZeroWeightedDistributions/src/ZeroWeightedDistributions.jl