'read_all()
Read all data until EOF; may block.'

def test_read_all_A(self):

    want = [('x' * 500), ('y' * 500), ('z' * 500), EOF_sigil]
    self.dataq.put(want)
    telnet = telnetlib.Telnet(HOST, self.port)
    self.dataq.join()
    data = telnet.read_all()
    self.assertEqual(data, ''.join(want[:(-1)]))
