Replace geography.geom_coverage with geography.geom_coverage()

[juanluisrto]

To see the area covered by the geography of a dataset, we can call

Dataset.get("dataset_id").geom_coverage()

and the output is a nice cartoframes map.

However, this is not working with geographies, where Geography.get("geom_id").geom_coverage() method does not exist. What does exists is the attribute Geography.get("geom_id").geom_coverage, which outputs a useless binary object.

Can this be fixed?

[Jesus89]

The dataset.geom_coverage() loads the WKB data from the geography.geom_coverage and this is not compatible with a map geography.geom_coverage() because it's already defined as a property.

The solution is really simple to implement (it requires renaming the property), but I would ask @alejandrohall @xavipereztr for the original reasons of the current implementation. Also, feel free to provide a PR with the change