graphutils: tiny update plus documentation
graphutils: tiny update plus documentation

RDFLib/rdflib,ssssam/rdflib,avorio/rdflib,marma/rdflib,yingerj/rdflib,RDFLib/rdflib,avorio/rdflib,armandobs14/rdflib,marma/rdflib,yingerj/rdflib,dbs/rdflib,RDFLib/rdflib,avorio/rdflib,marma/rdflib,avorio/rdflib,dbs/rdflib,armandobs14/rdflib,armandobs14/rdflib,ssssam/rdflib,dbs/rdflib,RDFLib/rdflib,dbs/rdflib,ssssam/rdflib,ssssam/rdflib,armandobs14/rdflib,yingerj/rdflib,marma/rdflib,yingerj/rdflib