needs to build a python 3.4 extension

With python3.4 as default, python-misaka fails its tests, as it does not yet build an extension for 3.4:

  http://people.canonical.com/~pitti/tmp/autopkgtest-py34/fail/py34-python-misaka/results/

======================================================================
ERROR: Failure: ImportError (No module named 'misaka')
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Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/nose/failure.py", line 38, in runTest
    raise self.exc_val.with_traceback(self.tb)
  File "/usr/lib/python3/dist-packages/nose/loader.py", line 413, in loadTestsFromName
    addr.filename, addr.module)
  File "/usr/lib/python3/dist-packages/nose/importer.py", line 47, in importFromPath
    return self.importFromDir(dir_path, fqname)
  File "/usr/lib/python3/dist-packages/nose/importer.py", line 94, in importFromDir
    mod = load_module(part_fqname, fh, filename, desc)
  File "/usr/lib/python3.4/imp.py", line 235, in load_module
    return load_source(name, filename, file)
  File "/usr/lib/python3.4/imp.py", line 171, in load_source
    module = methods.load()
  File "<frozen importlib._bootstrap>", line 1229, in load
  File "<frozen importlib._bootstrap>", line 1209, in _load_unlocked
  File "<frozen importlib._bootstrap>", line 1133, in _exec
  File "<frozen importlib._bootstrap>", line 1436, in exec_module
  File "<frozen importlib._bootstrap>", line 321, in _call_with_frames_removed
  File "/tmp/adt-run.ivOEmn/dsc0-build/python-misaka-1.0.2/tests/misaka_test.py", line 11, in <module>
    import misaka
ImportError: No module named 'misaka'