Annotate queries that mention spatial literals.

[Aklakan]

LSQ should annotate queries that contain spatial literals with at least a bounding box of the union of those literals.
This would allow browsing queries on a map and seeing which areas they affect.

SELECT  (count(*)  AS ?c)
WHERE
  { GRAPH <http://www.example.org/graph/1>
      { BIND("POLYGON((-78.75 -90, -78.75 -78.75, -67.5 -78.75, -67.5 -90, -78.75 -90))"^^geo:wktLiteral AS ?queryGeom)
        ?feature  spatial:intersectBoxGeom  ( ?queryGeom ) ;
                  geo:hasGeometry       ?featureGeom .
        ?featureGeom  geo:asWKT         ?featureGeomWkt
        FILTER geof:sfIntersects(?featureGeomWkt, ?queryGeom)
      }
  }