added note to why we're importing ConjunctiveGraph as Graph
added note to why we're importing ConjunctiveGraph as Graph

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