More flexible way of loading `GeoPressureViz` data

[Rafnuss]

The only way I can find to use data in a shiny app is to save the data in a .RData in a specific folder (~) and then read it from the app. I cannot find a good way to pass variable to a shiny app instance Any suggestion?

[Rafnuss]

This is actually possible using the global variable https://community.rstudio.com/t/pass-variables-to-shiny-app/1950

[Rafnuss]

solved with #52