Initial work on location inference #75
Added SpatialRelations NS
Handles SpatialRelations.within
Protection against infinite recursion
Use new helper in oxpoints importer
Fix bug in ordering -- prefer "physical" relations rather than org
Simplify method
Updated unit tests class name
Added method to find shape of a Thing
Added some documentation
Make sure that a Building would not get the shape of a Site
Removed debug comment
Merge pull request #83 from ox-it/oxpoints-location-inference

OxPoints importer location inference