Rendering query strings with interpolated bindings

[RickMoynihan]

We currently support interpolating bindings, but we don't provide a method to see what was interpolated. Add way to preview bindings with this:

http://docs.rdf4j.org/javadoc/latest/org/eclipse/rdf4j/repository/sparql/query/QueryStringUtil.html#getQueryString-java.lang.String-org.eclipse.rdf4j.query.BindingSet-