oort.rdfview.ExecCache:
This is a query execution cache which reuses results for the same query,
subject and language, avoiding multiple instances of the same query when
given the same subject and lang.
oort.sitebase.MultiBaseResourceViewer:
Use for full-fledged apps where many different base URIs will be
"mounted" at different named bases (done with the dictionary
resourceBases).
oort.sitebase.ResourceViewer:
Use for simple apps where all URIs in the graph share the same base URI
(set resourceBase to that).