implement and unit test TriplesParser / TriplesSerializer

[sammefford]

// A result that contains triples.  Usually this result will be used to populate
// Sesame RDF or Jena RDF, but we provide a simple interface to wrap Triples.
// Thus while there are Javadocs for the following interfaces, we expect them
// to be used only by the two client projects, Jena and Sesame.
public interface TriplesParser {
    public void parse();
}
public interface TriplesSerializer {
    public void serialize();
}
public interface TriplesParsingHandle extends TriplesReadHandle, SPARQLReadHandle {
    public void populate(TriplesParser parser)
}
public interface TriplesSerializingHandle extends TriplesWriteHandle {
    public void serialize(TriplesSerializer serializer)
}

[sammefford]

We determined this is not required, as we will just create new Jena and Sesame-specific handles