backends are now responsible for storing prefix to namespace bindings
backends are now responsible for storing prefix to namespace bindings

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