Add inner and outer members of boundary and multipolygon relations

[1ec5]

This query shows that no boundary or multipolygon relation in the OSM Planet dataset has osmrel:members that are ways with the role inner or outer. The only members in the dataset are label and admin_centre nodes, subarea relations, and plenty of tagging mistakes. This makes it difficult to perform tasks such as:

• Comparing the perimeter of a building that has a courtyard to the perimeter (P2547) property on Wikidata
• Computing the perimeter of a boundary, for example to apply the Poslby–Popper compactness test to the boundary
• Associating a disputed boundary claim line with a boundary relation
• Finding murals on walls of buildings that have courtyards

Also, in this OSM discussion, I needed to access the ways that make up a boundary relation in order to determine the total set of ways that would be part of a proposed time zone relation. I had to drop down to Overpass, which has various recursing operators as well as a length() operator.