Fix default encoding problem in setup.py under Windows.

    Traceback (most recent call last):
      File "setup.py", line 15, in <module>
        long_description = fd.read()
     File "C:\Python33\lib\encodings\cp1251.py", line 23, in decode
        return codecs.charmap_decode(input,self.errors,decoding_table)[0]
    UnicodeDecodeError: 'charmap' codec can't decode byte 0x98 in position 1577: character maps to <undefined>