RDFPipe: added docstring, optparse description and version.
RDFPipe: added docstring, optparse description and version.

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