Comment 2 for bug 1716968

When passing a signed message in as a UTF-8 string (decoded from bytes):

Traceback (most recent call last):
  File "./dmarctests.py", line 45, in <module>
    print("VERIFY: ", dkim.verify(signedmsg.decode('utf-8')))
  File "/usr/lib/python3/dist-packages/dkim/__init__.py", line 628, in verify
    d = DKIM(message,logger=logger,minkey=minkey)
  File "/usr/lib/python3/dist-packages/dkim/__init__.py", line 318, in __init__
    self.set_message(message)
  File "/usr/lib/python3/dist-packages/dkim/__init__.py", line 358, in set_message
    self.headers, self.body = rfc822_parse(message)
  File "/usr/lib/python3/dist-packages/dkim/__init__.py", line 207, in rfc822_parse
    lines = re.split(b"\r?\n", message)
  File "/usr/lib/python3.5/re.py", line 203, in split
    return _compile(pattern, flags).split(string, maxsplit)
TypeError: cannot use a bytes pattern on a string-like object