Add tot_grid_count and bounding box corners coordinates to get_studies_by_country API
Remove trailing whitespaces and check parameter iso to be 3 characters long
Add API to get building fractions and dwelling fractions for a given study region id
Use parametric study region id in query
Merge branch 'ged-add-api-to-list-countries-and-subnational-regions' of https://github.com/gem/oq-platform into ged-add-api-to-list-countries-and-subnational-regions
Merge branch 'ged-add-api-to-list-countries-and-subnational-regions' into exposure-export-UI-changes
extend the application to discriminate based on grid count