- moved/merged _fetchBoundLeaves into rdflib.sparql.Query - fixed Union logic for Union(..,pre-evaluated expression)
- moved/merged _fetchBoundLeaves into rdflib.sparql.Query
- fixed Union logic for Union(..,pre-evaluated expression)

git-svn-id: 60eb48102d1ca0c284ab3654bef916b01e1b221b@1214 4f84a9ca-5c3e-0410-8a68-0bdf370325d5

nwebs/rdflib