Updated rdflib.

[ocefpaf]

#2015/02/19 RELEASE 4.2.0

This is a new minor version of RDFLib including a handful of new features:

• Supporting N-Triples 1.1 syntax using UTF-8 encoding
  #447,
  #449,
  #400
• Graph comparison now really works using RGDA1 (RDF Graph Digest Algorithm 1)
  #441
  #385
• More graceful degradation than simple crashing for unicode chars > 0xFFFF on
  narrow python builds. Parsing such characters will now work, but issue a
  UnicodeWarning. If you run python -W all you will already see a warning on
  import rdflib will show a warning (ImportWarning).
  #453,
  #454
• URLInputSource now supports json-ld
  #425
• SPARQLStore is now graph aware
  #401,
  #402
• SPARQLStore now uses SPARQLWrapper for updates
  #397
• Certain logging output is immediately shown in interactive mode
  #414
• Python 3.4 fully supported
  #418

Minor enhancements & bugs fixed:

• Fixed double invocation of 2to3
  #437
• PyRDFa parser missing brackets
  #434
• Correctly handle \uXXXX and \UXXXXXXXX escapes in n3 files
  #426
• Logging cleanups and keeping it on stderr
  #420
  #414
  #413
• n3: allow @base URI to have a trailing '#'
  #407
  #379
• microdata: add file:// to base if it's a filename so rdflib can parse its own
  output
  #406
  #403
• TSV Results parse skips empty bindings in result
  #390
• fixed accidental test run due to name
  #389
• Bad boolean list serialization to Turtle & fixed ambiguity between
  Literal(False) and None
  #387
  #382
• Current version number & PyPI link in README.md
  #383