add reference to other mathematical models to other diseases

## alternative 1

Add reference to other mathematical models to other diseases: [Zika at epimodelac](https://epiverse-trace.github.io/epimodelac/ZIKAB.html), [TB at reconlearn](https://www.reconlearn.org/post/practical-tb), the [epirecipes repository and CRAN task](https://epiverse-trace.github.io/epidemics/#related-projects) (possibly, make a table of diseases covered! Ebola, difteria, Zika, TB, etc…)

## alternative 2

with the goal of keeping the learner within the ecosystem, we can redirect to {odin} which is a wider library of models.

- redirect to odin prototyping https://github.com/epiverse-trace/epidemics/issues/222
- odin basic models https://mrc-ide.github.io/odin.dust/articles/sir_models.html

possibly to fix in #34