Example data

[simon-smart88]

Various options for this:

• one button on the front page which loads a shapefile, covariates and aggregation raster. This could also launch a walkthrough of the whole analysis
• options within the *_upload modules to load data individually (as know)
• separate modules for loading various example datasets e.g. at least some different examples of response data which they could then use for analyses

[simon-smart88]

@timcdlucas I've created a separate module for loading example response datasets - so far madagascar and the new york and scotland datasets from {SpatialEpi}. If the user selects the madagascar dataset then they'll also be able to load the example covariates and aggregation raster inside the relevant modules