Bytearray test hack

[thijs]

See first failing test for Jython:

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ERROR: test_byte_array (test_amf3.DecoderTestCase)
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Traceback (most recent call last):
  File "/home/buildbot/slaves/pyamf/amd64-ubuntu-jython/build/pyamf/tests/test_amf3.py", line 856, in test_byte_array
    self._run([(amf3.ByteArray('hello'), '\x0c\x0bhello')])
  File "/home/buildbot/slaves/pyamf/amd64-ubuntu-jython/build/pyamf/tests/test_amf3.py", line 651, in _run
    e.run(self)
  File "/home/buildbot/slaves/pyamf/amd64-ubuntu-jython/build/pyamf/tests/util.py", line 86, in run
    testcase.assertEqual(self.decoder.readElement(), n)
  File "/home/buildbot/slaves/pyamf/amd64-ubuntu-jython/build/pyamf/__init__.py", line 495, in readElement
    return func()
  File "/home/buildbot/slaves/pyamf/amd64-ubuntu-jython/build/pyamf/amf3.py", line 1196, in readByteArray
    buffer = zlib.decompress(buffer)
  File "/usr/local/src/jython-trunk/dist/Lib/zlib.py", line 52, in decompress
    return _get_inflate_data(inflater)
  File "/usr/local/src/jython-trunk/dist/Lib/zlib.py", line 152, in _get_inflate_data
    l = inflater.inflate(buf)
java.util.zip.DataFormatException: java.util.zip.DataFormatException: incorrect header check