add tests for details result formatting and trim results

Values that are None are no longer included in the output to save
a bit of bandwidth.

nominatim/api/__init__.py

@@ -20,6 +20,7 @@ from .status import (StatusResult as StatusResult)
 from .types import (PlaceID as PlaceID,
                     OsmID as OsmID,
                     PlaceRef as PlaceRef,
+                    Point as Point,
                     GeometryFormat as GeometryFormat,
                     LookupDetails as LookupDetails)
 from .results import (SourceTable as SourceTable,