API redefines CAMARA common datatypes without renaming #85

Problem description
API redefines CAMARA common datatypes without renaming them.

NOTE: the same problem occurs in Population Density Data API. The 2 APIs should align on their local definitions.

Expected behavior
Define local names for schemas that clash with CAMARA common datatypes.

• Area --> e.g. GeoArea (or GeohashArea)
• Area type --> GeoAreaType (or GeohashAreaType)
• Polygon --> GeoPoligon (or GeohashPolygon)

or some other different names.

Additional context
As this is a misalignment with Commonalities, it must be fixed before release.